Did you find our TOS sticky threads ? Those are very helpful for a crash course as well as a Drs & Pts sticky..

It sounds like some advanced PT or even expert chiropractic might be helpful, especially if you were just fine before the accident.

If TOS it can take time and if high pain, probably meds & injections /blocks might need to be looked into.
But experts are best so you don't get injured more.

Poor or inexperienced PT can make yo much worse.