Possible allergic reaction?

I’m a pretty heavy energy drink consumer. However I’ve been taking a break from them. Today I opened up a rockstar and drank it like normal. I usually drink throughout the day so it just stays open and not refrigerated wherever I’m at. I had some rockstar left and I wanted to finish it tonight. For some reason it tasted spicy? Like it was burning my tongue? But I kept drinking anyway. And now my throat has been kind of numb for the past hour. I can breathe ok, no other symptoms. Took some benadryl, no change. So what could this be?