Temperature levels symptoms and conditions

I have been on 50mcg levothyroxin for 3 yrs. I recently have been having many side effects that occur on a daily basis such as: migraines, leg cramps, crazy menstraul periods, dizziness (which I believe is from low blood surgar levels), body temperature levels, unable to sleep at night, and an upset stomach. I am going to go to a doctor and get this all figured out because I am miserable. I am not someone you want to be around at night because I am extremely tired and not able to function even sometimes during the day I get that way. Thanks for this site cuz I was having all of these side effects and not sure from what but it all makes since now.