Tomato allergy - unique reactions? I'm italian and had tomato sauce all my life.

Get tested. Before you give up on tomatoes, get an ige blood test to see if you are allergic. Immunocap offers such a test. You can get it at quest labs. Maybe you are just having heartburn from the acid?
M.D. visit/workup. I would advise a detailed history outlining your intake and then possible reactions. If it is consistent with an allergic response, testing can be performed.