What happened to my body when I partied that night?

One time I was hanging out with my friends at a birthday party and I was drinking alot. I was really drunk and in my stupor I was asked to take a smoke of marijuana. I did and when I was going to take a second pull something in my mind just told me to go home right that minute. When I got home my head was swooning and I felt a really bad pounding in my head like a jackhammer. My heart was beating faster and faster and I got really anxious and excited. I actually thought I was dying. I woke up my parents, yelled and screamed at them to give me water. I threw up and I damaged my both feet on hard concrete while on my knees throwing up. After ( with help from my parents) they put me to lie down and when I woke up I was fine…but extremely embarrased. Can someone tell me what exactly happened to my brain when I took that stuff?