I'm 36 weeks, and my doctor told me to watch out for that as it's one of the signs of pre eclampsia! Cramping between rips and breast area!
Is baby head down yet? I read when there's similar pain like that could mean that baby is still head up. Ask ur doc at ur next appointment. Good luck :)
It's likely baby kicking you. If it really starts to worry you go get it checked out but it sounds like baby just trying to stretch out.