I agree with you!
Your symptoms indicate * hypothyroid/hashimoto's and 40-50 years ago,
you would have been treated for hypothyroidism likely right away!
You still need the ultrasound to help determine the nature of the enlarged thyroid.
Your prediabetic diagnosis is also related to hypothyroidism and you need to pay a lot of attention to it.
Fluctuations in blood sugar levels drastically affect thyroid function.
Proctocolitis should be further investigated to find the cause, if possible
Your swollen lymph nodes and high CRP indicate inflammation or infection, which could be- or not- linked to the protocolitis, if it's caused by an infectious condition.
*Your thyroid serum tests were likely T4 and TSH and maybe T3.
They only indicate serum levels not thyroid function.
For this you need Free T3, Free T4 and reverse T3.
You can also do your own self-test, by doing Dr. Barnes Basal Temperature Test.
Just look it up online and follow the simple instructions precisely.
Do not fear or worry my dear. This should be simple, but it gets unnessecarily complicated because of the way the conventional system works.
Watch your diet, avoid sugars and go low carb, consume wholesome low glucemic nutrient rich foods in small frequent meals.
Exercise to your ability everyday, even if it only involves walking.
You can prevent becoming diebetic.** Get your thyroid regulated
My wife was a clinical dietician and facilitated this for many patients.
** If you can afford a holistic/naturopathic doctor, please consider it.
It could possibly save you a lot of pain and suffering,
After all, time is also part of our lives. Why wait longer while suffering?
You waited long enough, to my opinion.
I hope this helps and let me know if you need any more details, however,
please note that my comments and suggestions are not intended as a substitute for medical advice.
All the best.