Ay mamsh, that bubbling sensation around 19 weeks could be baby movements na, lalo na kung first time mo talaga ganitong feeling! Some of us moms say it feels like gas or bubbles muna before it becomes those proper kicks, kaya normal lang yan. That said, since you're FTM at gusto mo sure, best to mention it sa OB mo next visit para ma-confirm na it's your baby doing his/her thing, walang harm sa pag-ask, yan ang peace of mind na kailangan mo ngayon!