Baby in ribs? 21 weeks

Okay so I’m 21 weeks. I thought baby is supposed to be by my belly button? He is DEFINITELY moving in my ribs. I feels movements really low too which is why I’m confused. It’s not muscle spasms or anything, it’s 100% the baby. Is he just a big baby or is this normal? I don’t have a doctors appointment until next week so I figured I’d just ask here first