Hi, I Made A Deep Cut On My Middle Finger

Hi, I made a deep cut on my middle finger while working on my project for chemistry. Blood started gushing out so I went to wash my hands. I think I blacked out for a moment because next thing I knew I woke up to a hard bang on my head and I was laying on the floor. My head had hit the shower door frame and there were noises in my ears and I was really dizzy. I went to go lay down and I could have sworn that it felt like I was hallucinating and washing my hands and hitting my head felt like a dream. After a while, my ears stopped ringing and my head stopped hurting. Then I felt my forehead and I felt a dent on my head. About an hour later, I was in church, and I started to feel nauseous again while standing. Then I went home and laid down and my mom gave me Tylenol and I feel much better now. However, the dent now is starting to bruise. I didn't tell my parents because I didn't want them to worry so my question is: will I randomly black out again and will the dent bruise go away?