DONT EVER GO TO THE ER WITHOUT INSURANCE!!!
Ice 20 min on, 20 min off for three days, then for a day or two keep a heating blanket on it.
Take 600mg - 1200mg of ibuprofen daily, or 1000mg of naproxen daily, or 1100mg of naproxen sodium daily, and 2-4 lortabs or percocets daily (if you have access to them), if not I find that advil geltabs are the best over the counter pain reliever. Opiate based painkillers work the best, but are the most addicting so be careful.
You should also try to stretch a little bit as well, and keep that leg elevated.
I’m guessing you may have slight cartilage damage.
The icing and ibuprofen/naproxen/naproxen sodium will bring the inflammation down, the heat will relax and stretch out the muscle/cartilage, and the painkillers will, well, take the pain away.
If its hurting after a week the you’ll need a professional opinion.