Baby "Bump"

I'm 18w5d today and for the past, maybe 4 weeks now, my son will push his whole body against my belly. I feel when he does it on the inside and you can feel his body on the outside as well as see it. Does this happen to y'all too? Is there not enough room or something in there lol?

(This was the best I could get the pic before he went back down) he does it several times every day. And its not a kick its his whole body like he is trying to bust his way out lol