Question!?

Does anyone else get stomach aches when they are eating or right after you're done eating? I also get full sooner and can't finish my meal. Example: I just ate half of a chicken breast sandwich on wheat with spinach, tomato, bell pepper and mustard but I can't eat anymore do to a stomach ache. I know it's not that I'm eating unhealthy foods because I naturally crave veggies and protein. Just wondering if it's something I should worry about?