Could I have hypothyroidism?

I am 20 years old. About a year ago I was told I had hypothyroidism because my TSH was 5.5 but I was unable to continue going to an endo because I didn't have insurance. Anyways I took synthroid for a year until recently. I am now seeing a new endo and he wanted me to stop taking synthroid for 6 weeks so he can get bloodwork and see if synthroid is needed. For the last couple of months, I have had chronic headaches. My neck and shoulders always hurt. I also have lower back pains. I also have tingling in my legs, arms and ankles. The tingling lasts a couple of days stops and then comes back. It occurs mostly on my left but also occurs on my right. I just want to feel better.