Thanks for writing in. I dont think extreme weakness is due to Hashimoto's especially if your recent TSH
value was in normal range. If you not got your TSH repeated in recent past I suggest you go for it now. Weakness seems to related your recent bout of flu
. If your lab tests are all normal now I advise you to take multi vitamin supplements, calcium & vitamin D supplementation. You can also take vitamin B12
along with the above. Try this treatment for 2-3 weeks and if you find no improvement then consult a physician for proper evaluation and lab tests.
Hope this helps.