I'd like to chime in and play devil's advocate to the original poster.
You are 20 years old. You can run GH safely and effectively but given it's abuse on the joints since you play football I would go IM not sub Q and get an IGF-1 release instead of going for straight fat burning. If you do go Sub-Q I would keep it at a low dose say 2 iu's ED. 3 times a week administration post workout into the muscles you just worked out at a good moderate dose will help if you go the IM route. Make sure you inject bi-laterally. Shouldn't have to worry about thyroid down regulation too much to employ T-4 from IM administration.
As for T-3, scrap that idea. If you want to play with Thyroid hormones research T-4 and TSH output. This should point you in the right direction. If you run GH Sub-Q you better be running a small dose of T-4.