Braxton hicks..

Lacey • Mommy to an Angel 1.14.16; wife 9.24.16; rainbow baby 4.4.17 && Baby #3 Due 4.28.20
I'm sure his has been posted many times before... But... 
The odd time my stomach feels like it gets really tight and uncomfortable, then it goes away. I'm 29 weeks. Could this be Braxton hicks? Or just plain discomfort? (I also have extra amniotic fluid so I'm wondering if it's because of that). Thank you :)