Is Levothyroxine Given For Dizziness, Tiredness And Shortness Of Breath?

i HAVE BEEN UNDER ALOT OF STRESS FOR THE LAST YEAR. i HAVE HASHIMOTTOS DISEASE AND TAKE 75MG LEVOTHYROXINE ONCE A DAY. I HAVE BEEN EXPERIENCING CHEST PAINS ON AND OFF, SWOLLEN ANKLES, SHORTNESS OF BREATH ON MY NEW TREADMILL, AND WHEN CLIMBING STAIRS, DIZZINESS AND FOR THE LAST WEEK EXTREME TIREDNESS. IT'S AS IF THERE ARE WEIGHTS ON MY THIGHS.