Hypothyroid. Pain in my legs and hips.

I was diagnosed with graves disease last year.I was advised to take radiation therapy in December and was advised consult again in March but due to coronavirus situation I was not able to do that. I started experiencing leg pains in 1st week of March and it increased from then. By the 2nd week the pain increased to chest area also. I had myself tested mid March and my tsh level was 45, t3- 0.45 and t4- 3.07 at that time On 19 March I started taking Eltroxine. After taking it for 3 months I had myself tested again and now my tsh level is 15 but t3 and t4 level is normal. Now also I am not able to do any physical activity. Whenever I do any activity I get tired very fast and start experiencing pain in my legs and hips.