Questioning if it's actually IBS. More?

I am a worrier. I've gone to the doctor for a few different things I was convinced was wrong with me and each time they tell me it's stress and anxiety. I was diagnosed with IBS, no specific tests for that diagnosis though, just me telling my doctor my symptoms. I had a lot of blood work done, everything came back normal, doctor actually said excellent. I worry that the IBS symptoms I experience could be something different, like maybe my liver. If my liver enzymes were in perfect range, could I still have problems with my liver, like cirrhosis? Should I feel confident that I'm in good health and I just have digestive issues and nothing more? My brain goes to liver problems to bowel cancer to stomach cancer, etc.