Should I call my doc?

I'm a FTM & 29 weeks exactly. for the past few days I've had pain in my lower belly and on the sides of my belly, particularly towards then end of my shifts & afterwards. I had Braxton Hicks on Friday night when I got home from work, some were painful others not. 
A little background on my job - I'm a trainer at a weight loss facility so I'm constantly standing up, bending over, moving around & rarely get a chance to sit down and rest during my shifts. I haven't been doing a lot of demonstrations for workouts since I've been pregnant (Drs orders) so mostly just instructing. 
My question is are the pains normal? Could they be from working?? Should I call my obgyn?