Fat or swollen?

So, in two years I've had two different cancers, in October I had a double mastectomy, when my boobs had gone, I realised how big my stomach was!! Anyway, it might be in my head but I swear it's got slightly bigger, I've always been a big girl, didn't even lose weight when I had chemo etc, so i am worried about fluid in stomach or am I just fat!!!!!! Don't want to go doctors AGAIN