I am a really a nice guy, i never had an issue like this i enjoy life and people but i had a really serious experience ( no im not some kind of serial killer, i just had an unusual problem). OK i decided to buy an amp energy drink, first time i ever drank one just wanted to see what was so good about them. It was pretty good but then after a while i felt a SURGE of anger hit me and i felt really angry for some reason. I felt mad at the world, i hated everyone i saw and had nasty disturbing thoughts about people whom i didn t even know(strangers) i wished harm upon them which pretty much scared me. I talked to my girlfriend on my cell phone snapped on her and hung up in her face because she asked me to pick up bottles for my son. I murmured things about her calling her the b word and how bad i wanted to slap that B when i see her, of course i would never hurt my girlfriend i love her dearly but i became a different person. I was at walmart and a man stared at me for over 5 seconds i became disturbingly angry and was a few seconds away from punching him(wish i was joking but sadly im not). i felt like i was possessed or something and it freaked me out. i went home and punched my wall a few times till i was satisfied and went to sleep almost instantly, now that i have woken up i feel fine and decided to call my girlfriend and apologize to her. i looked it up on the internet and it seems i could have had a allergic reaction from the caffeine in my soda, but i want to confirm can caffeine really make you feel this way?