Ectopic thyroid is thyroid tissue outside of the thyroid gland. More than 99% of cancers occur within the thyroid gland. Most thyroid nodules are benign. 5% are cancerous. Ultrasound features that could indicate thyroid cancer: microcalcifications, solid nodule, size larger than 2 cm, coarse calcifications, more tall than wide, irregular borders and increased blood flow within the nodule. None of these signs are listed on your ultrasound.
See how you feel after your throat infection has been treated. I've had a throat infection for quite some time causing my right tonsil in particular to swell causing a lump in my throat on the right side. And then there are the tonsil stones ugh lol.
I will try to answer your question with what I know, but I am not a medical professional, just someone who has a thyroid problem (and have experience with having hypothyroidism and thyroid cancer).
Swollen lymph nodes are the most suspicious symptom you have listed, and honestly I am not a specialist on what a hypoechoic lymph node is or if that is more common with thyroid cancer versus a regular throat infection. Since you had a blood test that showed throat infection, it is possible your lymph nodes are swollen due to your immune response to your throat infection. I had several swollen lymph nodes pulled out of my "central compartment" of my neck during my thyroid surgeries, and while I did have thyroid cancer, all the lymph nodes were benign (I had 14 in total removed, all benign). In my case my lymph were swollen due to Hashimoto's, an autoimmune disease where your body develops antibodies against your own thyroid. I can tell you first hand, swollen lymph nodes in the neck don't always mean cancer.
As for thyroid nodules, most thyroid nodules (90-95%) are benign. At the size they are, the doctors may recommend a fine needle biopsy to determine whether they are benign or not. Most places in the US do fine needle biopsies on thyroid nodules when they are 20 mm or 15 mm with more suspicious characteristics. I don't know what they do in Australia, but there is a chance they will recommend "follow-up ultrasound" in 6 months to a year to see if they grow larger and then do a biopsy when they are a larger size. Lots of people have thyroid nodules, 20% of 20 year old women, 30% of 30 year olds, 40% of 40 year olds, etc., and most of these people will never know they have them unless they are found incidentally on an ultrasound or CT scan, or are large enough for doctors to find them on an examination, and most nodules are benign.
If your doctors suspect your lymph nodes are suspicious and not related to an infection, they may do fine needle biopsy on those as well as the nodules, but this is an area where I just don't know enough.
I am not familiar with ectopic thyroid, but it sounds like that is just normal thyroid tissue in places it is not normally found. It doesn't mean it is thyroid cancer, and from what I can find, it looks like ectopic thyroid occurs because of how the thyroid develops during embryological and fetal development. The thyroid starts as a bud near where the mouth and tongue will be (around day 16-17 of development), and then moves down to its position right above the larynx by moving down the "thyroglossal tract", and sometimes it leaves little remnants of the thyroid along that tract, which can be ectopic thyroid.
Your stuck in the throat feeling - this could be from your throat infection, it could be swollen lymph nodes pushing on other structures in your neck, or it could be your thyroid nodules pushing in on other structures of your neck. It doesn't mean thyroid cancer. Your nodules are pretty small to be causing a lot of pressure on your trachea or esophagus, but if you are having inflammation in your throat in general from an infection, that can cause a tight throat feeling.
Hypothyroidism symptoms - tired easily but all tests say normal. Have you been tested for Hashimoto's? Hashimoto's as I wrote above is an autoimmune disease where you develop antibodies to your own thyroid tissue. The test involves testing thyroglobulin (Tg) antibodies and thyroid peroxidase (TPO) antibodies; people with Hashimoto's will have high levels of either (or both) of those antibodies. Hashimoto's can cause both hypothyroidism and hyperthyroidism symptoms. As your immune system attacks the thyroid, less thyroid hormone is produced and you may have hypo symptoms. This causes your thyroid stimulating hormone to increase, telling your thyroid to grow and produce more hormone, and as it grows and makes more thyroid hormone (T4 and T3), you may have hyperthyroidism symptoms, causing your TSH levels to decrease. This can result in someone having lots of thyroid hormone related symptoms but showing up on the hormone blood tests as normal. If you haven't already, I would request getting Tg and TPO antibody tests for Hashimoto's. (When I was first diagnosed with Hashimoto's, my TSH, freeT4, and freeT3 were all "normal", but I had many hypothyroidism symptoms and I knew something was wrong so I had to push for the Hashi's test).
If you also wanted to share your thyroid hormone results, other people who know a lot about that can give there opinion. If the only thyroid hormone test they have done is TSH, that is not really a great indicator of thyroid hormone function, unless it is way off and clue people in that something might be wrong with the thyroid. Vitamin B12, vitamin D, and ferritin can all have an effect on thyroid hormone function in your tissues, so if you are feeling tired often, it might help to check those levels as well because that could also cause hypo-like symptoms if they are too low.
You can have a thyroid hormone problem causing hypothyroidism and not have thyroid cancer, and vice versa. I don't think hypothyroidism and thyroid cancer are all that well correlated, unless it is "chronic untreated Hashimoto's" which can cause multinodular goiter and may increase your risk for cancer (that's what I had, my thyroid was very large, and full of 1 to 2 cm nodules all growing in to each other,. Your thyroid appears to be a normal size with a couple nodules, so that is not what you have).
Please don't freak out. Nothing you have posted on here makes me think you have a high risk for thyroid cancer, but you definitely will want to follow up on the nodules and lymph nodes. If you are having hypo symptoms but TSH is normal, please ask your doctor to test your thyroid antibodies. I also think you should get freeT4 and freeT3 tested which will tell you more about how your thyroid is functioning, if those haven't already been tested, and get Vitamin D, B12, and ferritin checked.
I hope you feel better soon - I know trying to get a thyroid problem diagnosed can cause a lot of anxiety.