Plan B

Okay so me and my boyfriend had unprotected sex 2 weeks ago today. He said he pulled out in time but we decided I should take a plan b just in case. We didn't have one with so I went and got one the next morning. Two days later I got light headed and dizzy while in class. Then last weekend I had to take one again just in case. I'm on birth control and he never came in me. I've been kinda moody and crampy the last few days and today I got what seemed to be my period this morning but tonight now I'm not bleeding anymore. My period isn't due for another week. Could this all just be side effects from taking the plan b pills?