You do need to go to the doctor and get your thyroid regulated, but TSH is not what you have to worry about. You need to make sure you're on a large enough dosage of thyroid replacement hormones to increase your actual thyroid hormones to normal levels. The hormones you need to have tested are Free T3 and Free T4.
You need to go to the Dr to get your TSH levels regulated within normal levels. When those TSH levels are within normal limits-your metabolism regulates and you will lose weight.