Caught a cold, experienced memory-loss and vomited blood, in that order, in a short period of time. what could be wrong?

yesterday morning, I started to feel sick like I had a cold and in the evening, I knew that I had come down with something. I felt sick this morning, but I didn’t have a fever, so I went to school. I got through most of my first period, but had to go to the school clinic and take some DayQuil.
the next thing I remember after first period is throwing up in the bathroom, with no memory of going there. when I looked at the time and it was almost eleven o’clock, which is the time that third period ends. I had apparently been to second and third period and I actually have some notes and an assignment that I did during those periods.
I went back to the nurse and rested on a cot for about a half-hour and then decided that I didn’t want to stay at school. while I waited for my mother to pick me up, I threw up a couple of times and when I got home, I threw up blood.
I made a doctor’s appointment and it’s in about two hours, but I’m wondering if I should go to the ER…
any help would be much appreciated.