Why does the left side of my belly always feel bruised?

nmpg15235

In a certain spot, it always hurts when pressure is applied. I babysit and any time the kids accidentally hit my belly, it never hurts except for on my one side in that particular spot. 

The baby feels like hes always there but that shouldnt cause pain.  My stomach is also slightly larger on that side and has been since day one.  My stomach was symmetrical when I had my son years ago...  and I never had any "sensitive" spots.

 

Any idea what it is? My doc apt is next week but Id like to get some ideas in the meantime.