Advice

I had unprotected sex 07/08. I also took a PLAN B . I was also fertile at the time. My period is supposed to come next week. My boobs are sore. I’m guessing it’s PMS . My friends have been telling me I am gaining weight. I think that’s from all the snacking. I do look bloated. Is it too early to takes pregnancy test or am I just over reacting. Should I wait until next week for my period to come?