Pulled/torn stomach muscle

Hey ladies,

Wondering if anyone has had this before. I’m 25 weeks and went to a convention on the weekend which consisted of lots of walking and standing. The next day it felt like I pulled a muscle in my abdomen (near belly button) to the point where I’m whincing when I stand up or walking, it’s a tight feeling like you get after doing 100 sit ups.

Anyone else had this, could it be growing pains or did I push myself to far perhaps?