Causes of pain in lower right side above buttocks?

To answer that specifically, an exam from a doctor would have to be performed. The most common cause of such a pain that I've ever encountered was a sacroiliac subluxation. This means that the joint where the sacrum (the bone you sit on) and the ilium (the big round hip bone) come together is misaligned and causing the muscles in the area to pull. The most efficient way to correct this is to visit a chiropractor.