There are two categories of hypothyroidism: primary and central. Primary hypothyroidism is due to disease in the thyroid, with resulting increasing levels of TSH. The most common cause is autoimmune. It usually results from Hashimoto thyroiditis. With central there is a dysfunction in the hypothalamus/pituitary system resulting in TSH levels that are too low to adequately stimulate the thyroid gland to produce hormone, so FT4 and FT3 levels are also low.
It may be that you have central hypothyroidism, and that the autoimmune disorder shown by the TPO ab test is in early stages and not yet having a significant effect on the thyroid gland. Then there is also the possibility of postpartum thyroiditis that did not recover, leaving you hypothyroid.
Regardless of the cause, with those symptoms and those test results it is clear that you need a good thyroid doctor that will treat you clinically by testing and adjusting Free T4 and Free T3 levels as needed to relieve symptoms, without being influenced by resultant TSH levels. Note the words of an excellent thyroid doctor, "The free T3 is not as helpful in untreated persons as the free T4 because in the light of a rather low FT4 the body will convert more T4 to T3 to maintain thyroid effect as well as is possible. So the person with a rather low FT4 and high-in-range FT3 may still be hypothyroid. However, if the FT4 is below 1.3 and the FT3 is also rather low, say below 3.4 (range 2 to 4.4 at LabCorp) then its likely that hypothyroidism is the cause of a person's symptoms."
If you want to confirm what I have said, I highly recommend reading at least the first two pages of the following link, and more, if you want to get into the discussion and scientific evidence for all that is recommended. If you have a problem with your doctor getting diagnosed and started on thyroid med, you can also make use of the link by giving a copy to the doctor. If that doesn't work to get the needed diagnosis and treatment, then give us your location and perhaps we can suggest a doctor that has been recommended by other thyroid patients.
http://www.thyroiduk.org.uk/tuk/TUK_PDFs/diagnosis_and_treatment_of_hypothyroidism_issue_1.pdf
In addition, since hypothyroid patients are so frequently deficient in Vitamin D, B12 and ferritin, those need to be tested and then supplemented as required to optimize. D should be at least 50 ng/mL, B12 in the upper end of its range, and ferritin should be at least 100.
those were Free T3 and Free T4 scores