Got Blood Drawn Also Got My Second Shot For STD Prevention And I Keep Sweating Too. Treatment?

Hi, I am a young teen and this morning I got blood drawn. They took about three or four vials - which were about eight inches in length from what I could see. It was an annual physical so I was a bit surprised at how much they took. For reference this was early in the morning (around 9:20am) and I had not yet eaten or eaten in about twelve hours as my doctor recommended. I had been pushing fluids, though.
Anyways, I went to school after it was all said and done (side note, I got my second shot for STD prevention, so I don't know the symptoms) and I realized I was having trouble thinking/focusing. I was wide awake and I thought i was okay, but now that I'm home I don't remember half of the day.
I started to eat, having an apple, some crackers, proteins, etc. and I started getting congested and after eating my stomach became upset. I rested for about an hour, waking up sweating. Again I had more fluids, caffeinated because I thought I might be getting a tension headache, but it only made my stomach worse. I tried water, getting in more protein and again it made things worse.
I am having trouble concentrating right now, as well. I keep sweating and I might check and see if I am running a fever but I would like to know if you could give me an idea of what is going on.
Thank you.