my body needs HELP SOS.

Okay, this is kind of all over the place and whatever but I’m so embarrassed and over this - literally I NEED a new diet plan but it’s so hard to find one I am not over weight, I love my figure when I’m not bloated I have an amazing figure eight shape and a flat stomach and I love my body. ANY time I eat bread, cheese, certain meat, cereal, soups, like basically anything my stomach sounds like WWIII and I’m in SO much pain and I know one thing is that I’m sure I’m lactose but today I just ate a piece of BREAD and I was feeling so awful and sick and I just don’t know what to do. I feel so embarrassed to see a doctor or talk to my family because I really don’t want to sound gross and stupid, I just need a new diet but I have no clue what to do or what will work.