What you describe really fits the standard TOS symptoms.

I hope you can request a highly skilled & caring PT person... no beginners or bored PT person that won't really listen to you and make adjustments to treatment.

Many times they tend to have a standard therapy protocol and often it moves forward too fast for many of us w/TOS.

We tend to get delayed pain, so we do things then hurt more later on, so we need to learn what will be OK and what is not OK to do yet.

check out the Sticky threads near the top of the TOS threads page, tons of info.
things to learn about
Trigger points
Top rib mobilization
Posture issues ?? = forward head/forward shoulders

You may even benefit from an upper cervical chiropractor for a few sessions
(c1 c2 probably got misaligned during the impact)
http://www.upcspine.com/self.htm