I am having pain in my stomach, mostly from the bottom of my rib cage down to the belly button, on both sides. It feels as though my stomach is bruised on the inside and someone keeps pressing on the bruise. I am almost four months post-partum (3rd child) and this is the first time I'm feeling like this. I have been working out for almost two months now, and got a back massage on Friday for the first time. I started feeling like this the next day (Saturday), and this is now the third day with pain. I have been going to the bathroom regularly and don't feel nauseous at all, I just have this pain in my stomach that feels worse when I walk and lay on either of my sides. Any idea what this could be ? Thank you