Helpp ??

I know this may sound real stupid. But I'm 20 weeks & barely showing. Just looks like I have a pug. Could that mean that my son it's be growing properly ?? & also I feel a little crabby in my pelvic area. It's not crampy, not sharp or painful. Just a little crabby. Idk how to explain it. Like it feels hot. Not burning just hot. Lol idk how to explain it. Anybody else going through this ? My last doc appointment was when I was 16 weeks and he was measuring two days ahead. But now I'm just worried.