If you are Hypo, as determined by being tested for FT4 and FT3, you will have to be prescribed medication.
The over the counter "supplements" are nothing but a waste of money. NOTHING has hormone in it because the FDA prohibits the sale of anything without a prescription having any measurable amount of hormone in it.
Many of the supplements also contain Iodine. Which unless you are known to be iodine deficient , (not too likely in the USA with iodized salt) it can actually be counter productive (make things worse) for people who have Hashimoto's which is the #1 cause of Hypo in the developed world.
As asked above; How do you feel? What symptoms are you having?
If you have your blood labs please post them along with the reference ranges for each.
If you go back in for testing, INSIST and do not take no for an answer to get the "FREE T4 and FREE T3" tests done.
in addition you may also want to test for other things as well that are common to people who are hypo and cause fatigue. They are;
Vitamin D3 you want to be close to the upper end of the range of like 60
Vitamin B-12 again huge wide range and many people do not feel well until thie B-12 levels are well above half of the range if not towards the very upper end of the range
Iron & Ferritin
Was TSH all that was tested? If so, you should have follow up testing to verify hypo. FREE T3 and FREE T4 are the actual thyroid hormones and much more important than TSH, which is a screening test at best.
How do you feel?