plan B question

So ever since finals in May my period has been out of whack. I'm not on any sort of birth control and me and my boyfriend can be  irresponsible and don't use condoms all the time. Last weekend(Saturday)  we had sex and he wasn't sure if he had pulled out in time. Monday I got a plan B and I have been feeling weird ever since. I have had tender breasts, cramps only on my left side, thick discharge, nausea, and no period. I'm not sure if I haven't had my period yet because of the plan B or because maybe I took it to late. I have an appointment next week to get on the pill.. Any suggestions are helpful