Jolt in my heart followed by dizziness...?

Last night as I was trying to fall asleep I closed my eyes and 2 minutes later all of a sudden I felt this strong jolt in my chest that made me immediately open my eyes. First came the jolt, and a second later my head felt immensely dizzy but only for a few seconds. Dont know how to explain how dizzy I was but from a scale of 1 - 10 id have to say 10 :'( I freaked out a litte inside but I closed my eyes again. A minute later the same thing happened again. What could possibly be wrong with me ? Im a 16 year old lady.