Normal while angry what is this

Hey guys , I wanted to know. When im a useual quiet guy. But when I get mad I go completely crazy and people say that my pupils get huge and my eyes go red. Plus its kind of weird. I was at a social a couple of weeks ago and I seen someone I hated and for some reason it felt like I fell asleep I dont remember much. Just that my brother whom was there told me that I flipped out and veins were popping out of my arms , neck , head and hands. And I looked swollen. Plus he said that my eyes didnt look the same almost black. The weird thing is im a powerlifter and 300lbs is okay I can lift with it pretty good but when my uncle tried to take me out of the hall my uncle said that I picked him up and threw him on his back. And it took 25 people at the same time to drag me out of the hall. Itrs been scareing me ever since , am I crazy or something? Or a very angry person? , was it a blackout? , I just want to know what happened. And howcome my body did that. It was like I shut off emotionally.