So a couple of weeks ago I was off school sick due to not being able to swallow but got better and today I have a pain underneath my jaw?

See your MD. Sounds like you may have had and still may have some kind of upper respiratory infection going on. Often you can start with a viral one and get a secondary bacterial one. Thr soreness under the jaw is probably your glands which would indicate that your body is trying to fight off some infection. Best to see your md and get it checked out. Good luck.