Diziness and lightheaded after sudden p.

Just a few minutes ago, our dog, for the nth time, attacked me. He bit my right hand and wouldn't let go. I'm fine tho. Just a little scratch. But as some of you know, I have a low pain tolerance. As soon as our dog let go of my hand. I felt all blood rushed to my head. I felt dizzy and lightheaded. I tried to sit coz my world was literally spinning. But as soon as I sit, I felt myself having a seizure. I don't know how but I am half conscious while I'm shaking on the floor. A few minutes after, My body stopped and I decided to lie on our couch since I still feel dizzy. I still remember before how I had the same attack when my mother accidentally (it was really an accident) punched me on my stomach. Same thing happened when I had an accident in our school.