Low alcohol tolerance?

I’m trying to diagnose myself. I don’t drink often but sometimes when I do, I seem to get a bad allergic reaction. Red hot itchy irritating skin for 1-2 weeks (usually upper body only, not on the face). This only happens when I drink up to a certain amount, though. If I have a casual few shots or a few beers, I’m completely fine. But it seems like after a certain point (maybe 5-10+ shots), it happens. I’m not even drunk at that point either. Anyone know what’s going on? Btw I’m not allergic to anything.