Back pain

Hey guys I’ve been searching around but I can’t find anything to answer this question so… My back feels like someone took a golf club to it several times, and I’m fairly certain that it’s from hopping around on my Uni. It’s not a spine thing, just the muscles in the mid-left section of my back REALLY hurting. I ride right foot back, and hold the handle with my right hand which, from what I’ve read, is unusual… Is this something I’m just gonna have to live with, or am I doing something wrong as far as posture/technique goes to cause this pain?