Can tight, spasming hip, butt, low back muscles on one side cause leg to hurt? Had steroid shot in butt gave a little relief but still feels crampy

Spasm. Absolutely, spasm can reduce blood flow and cause pain/aching in the leg. Not sure why you had the steroid IM shot though. Consider getting your low back looked at by a chiropractor or a DO who knows how to manipulate. Odds are you have a structural issue somewhere below L2. Soak in a hot bath then do some gentle stretching exercises.