Severe headache/dizziness after excercise?

I just began a kickboxing program. I am not really a fit person and have not excercised for a long period... the first day I went in we began with skip-ropes, I did pretty well. However, right after, it was as if my head was going to pop, my vision became extremely blurry and I had to go outside and sit down for like 15 minutes. I noticed that my eyes became very red. Of course, it improved, however, my head still hurts after a day and a half... I am not sure what to do.