It's extremely important to have your FT3 and FT4 levels tested. T3 and T4 are the actual thyroid hormones and indicate thyroid status mush more accurately than TSH. TSH is influence by many factors other than thyroid hormone levels.
If you are feeling overmedicated, you should request FT3 and FT4 ASAP. Adjusting meds on the basis of TSH alone is like flying blind. Perhaps you could ask your current doctor to order FT3 and FT4 and a new TSH. The clinic should want to see those anyway, and you can save some time by showing up to your appointment with current labs in hand.
When was your last meds increase, and how much of an increase was it? Have you been increasing on a fairly aggressive schedule?
My last blood test before today my TSH was 9.9 I do not have FT3 or FT4 results, yes I am a bonny lady but I still think I am on to high a dose and having reactions to my tablets.
Thanks
What is your TSH? Do you also have FT3 and FT4 and their reference ranges?
300 mcg is a very large dose...are you a large person?