I fell hard 2 weeks ago on sacrum-coccyx area; slipped going down a hillside onto a piece on concrete. It was excruciating the first few days and i have been taking intermittent vicodin (3/ day initially, now usually 1 in afternoon/ eve.It feels like I m sitting on something & hurts to squat, bend over or straighten up. I can t lay down flat or firm surface, but can sit better on firm surface. Initially it hurt to go up stairs, but that has improved. Last night at 4am I woke with an intense right-sided headache that improved with standing. I finally went back to sleep with a lot of pillows, laying towards the left side (after about an hour). Could the HA be related? I had neck pain which improved after I saw my chiropractor.