thanks ladies this is comforting to know
I went through the same thing. It freaked me out like something was wrong. It was right around 13-14 weeks i think. The belly is back now!!! Everyone keeps saying how popped out I am already. Dont worry about it. I think this probably happens to everyone as their body changes for baby
my stomach appeared to "drop" at 15 weeks as well.. enough for me to notice, at least. i think it does have to do with the amount of bloating, which i definitely think was making my stomach appear fuller one week and less so the next.. it has been filling back out though and then some, so i don't think you have anything to worry about ;)