Could Sharp Pain From Buttock To Back While Bending Indicate Pinched Nerve?

When I leaned over to pick something up, a sharp pain went from the top of my buttock to my back. It is painful to bend. Is this a muscle pull or maybe a pinched nerve? Aspercreme and ibuprofen seemed to help, but after lying down for a while it was very difficult and painful to get up. Should I apply moist heat? Thank you.