Pain in lower/centre back after car crash?!

I was hit up the back and taken to hospital on a spinal board because the pain in my neck was in a "worrying" place. luckily the xrays of the neck were clear. i was in shock in the hospital and just wanted to go home, i didn't tell the doctor i was feeling discomfort in the centre of my spine too.. which i know is bloody stupid but to be honest it didn't hurt that bad. but now it's quite painful.
i don't know whether to go to the doctors about this, because this could just be whiplash and i don't want to waste peoples time.. has anyone had this before?