Dr.baker says my symptoms line up w/ a othopedic and neurologic injury-is it normal for pain to go from shoulder down to my hand from car accident?

Perhaps: You may have a combination of shoulder joint trauma such as rotator cuff tear, and a stretch injury to the brachial plexus, and that might explain radiation of pain. But you could also have a neck injury which could also be referred down the arm. Whether this is thoracic outlet syndrome, cervical radiculopathy needs sorting out. Talk with your doctor.

Very frequent: This could easily comefrom injury to TMJ which would allow this connection.

Ortho or Neuro?: Pain from the shoulder to the hand may represent an injury to the nerves - these arise from the neck, travel under the arm, and into the arm. The brachial plexus (under the arm pit) is also a place where an injury can cause these symptoms. It is hard to say which is the cause- orthopedic or neurological, but both are possible.