The baby can be kicking and punching at 17 weeks.its also probably due to the way the baby is layed,they like to get into a comfi position,somtimes this is right against your ribs,I suffered alot with it.he or she will move.
Same thing happened to me. But according to my doctor, the baby is still too small to really be kicking or anything like that. Instead, it can be explained by your muscles, organs and ribs being moved around to make room for your growing baby and uterus. Like she said above me, there's not much you can do. In my case, the pain actually got worse as my baby grew. However, I'm more than 38 weeks now and I can say that since week 35 or so my ribs haven't really hurt. I hope it goes away for you!
Its probably the baby kicking or punching your ribs. There isn't really anything you can do to stop it, however you can try taking tylenol to dull the pain.