Oral test to diagnose?

has anyone been diagnosed by doing an oral test? that is, have you been in a Dr office and had a reaction and based in that, they diagnosed you? I have Kaiser, and they are the absolute worst. allergy will only diagnose based on tryptaste levels. after many GI tests, I finally have a GI referral. I'm thinking of bringing food I react to so they can see me have a reaction. I'm tired of being gaslit and this is ruining my life. I just want someone to listen to me, even if that means projectile vomiting all over the doctor's office.