A related discussion,
What dosage should I take was started.
You still have under-treated hypothyroidism. A specialist should be able to help get this under control more effectively, but essentially you need a higher dose than 75mcg as the target TSH is about 0.5-2.0.
Many of us who have experienced TSH levels as high as you have often feel very cold, sluggish, depressed, and have *no* energy.
I would suggest that you find a good endocrinologist who specializes in thyroid conditions (some only treat diabetes). Endocrinologists are specialists in regulating endocrine levels, unfortunately it is a specialty that many PCP and other physicians do not understand.
Med. dose should be increased until your TSH reaches acceptable level or to where you feel your best, within the Labs reference range. Retest every 6 to 8 weeks after starting each new med. dose. Also suggest to be treated by a doctor who deals in thyroid and treats many patients yearly.
Good Luck!
T-4 is affected by estrogen and should not be used to dose.
Ask for a FT-4 in addition to your TSH and maybe even a FT-3 to make sure you are converting the Synthroid properly.