Distended Stomach/CSection? Hormones?

I am 38 yrs young, had my gall bladder removed 13 yrs ago and recently had a C-section ( 7months ago).  Each month since then, I have a regular period and my stomach goes flat for about 7 days.  After that, without changing my diet and on the same exercise, my stomach is distended beyond imaginable. It is so big that my husband said that it looks like I am pregnant again!  He is worried and at this point, I am getting there.  I thought that it might be hormonally connected?  

I never had a C-section so I thought that this could be a result of post op?  I am never in pain, I cannot eat dairy- so I stay away from it, but the area beneath my sternum to the area above my belly button is distended however the lower part- flat as a pancake.  It looks really weird.  

Is there something that I can take to prevent this type of bloating?