I hit my head on pavement and now my neck is killing me any help to what might be wrong?

This is the second time i've done this the first time was two weeks ago from the ice This time my friend was helping up and thought it would be funny to drop me. ( i was somewhat drunk i admit) and i fell my spine rolled as i flatted and my head cracked on the ground and bounced then hit again. I about cried my head felt like a metal ball just scrambled my brains after a bit it stopped hurting but now a few days later. my neck in the front hurts really bad anytime i expand my throat say to "swallow food, cough, yawn ect." it hurts to turn my head.

So then i noticed when i lean my head forward and lean it to the left there is a huge knot in my spine and when i do the same and lean my head to the right there is nothing?

So what i might i have done? and should i got to the doctor?