I recently had unprotected sex Last Sunday which was January 15. me and my boyfriend went to go buy the plan b one step and I did feel a bit dizzy. It's been exactly one week and one day and yesterday I got my period, but my period isn't normal it's lighter than usual, and the color looks like brown not red. Is this normal?

Every morning I also wake up with a weird feeling in my stomach, I don't know what's wrong with me. Help anyone?