Hi Mike
Sorry to hear that you're having this much pain ....
so you understand it a little better, i'll tell you a little about 'backs'.
Your spine is of your 'central nervous system' and although you may have hurt your shoulders and neck, it may feel that you've 'hurt' your brain too .... as these area's are all connected with one another ... but then, so is your big toe .... have you ever banged your big toe, and felt sick afterwards or got a headache ... all the nerves are connected with one another....and they all send messages to the brain.
as Rich as suggested, see a doctor about your concerns, and they'll give you anti-inflammatories (to reduce any swelling) and put your mind at ease....
Also 'the girlfriend' suggests, try an ice pack on the area that hurts, don't leave it on too long, as you'll end up with 'frost bite'

but this will reduce any inflamed muscle / tissue and make it feel easier, and less painful .... but please see a doctor ....
You take care, and keep intouch..
Ginger