extreme sternum pain

I was jumping on a trampoline yesterday with my boyfriends brothers, and I flipped (involuntary) and landed on my head. this motion snapped my neck backwards, and caused EXCRUCIATING pain all through my neck and back. I layed flat for a while because it knocked the wind out of me, and my arms were tingling. After about 5 minutes, I got off the trampoline, and sat in a chair. While walking it felt as though something was pinching in my back. I went inside and layed down with a heating pad on my back, and fell asleep. This morning I woke up to find that my back pain was either gone or dulled by the horrible pain in my sturnum. When I breathe in too deeply, it hurts really bad. As it does when I cough, walk, or make any sudden movements. It is very hard for me to sit or lay down because of the pain. I have been searching online for anything about sternum pain, but all I can find is information about McNairs current sternum bruising. I don’t know if I need to be going to a doctor, or if this would be like having a bruised rib, in that there is nothing you can really do except aviod any strenuos activity. I would appreciate any advice anyone can give me. Thank you.Ashlee