is it normal to spot for 3 days after period ended?

I had a pregnancy scare back in February. I'm on the pill. My boyfriend stuck his penis in me once or twice without the condom on and then took it out. Well, since then I have had TWO periods that lasted 5 days and were both on time. I also took a pregnancy test the day before my second period was supposed to arrive just to make sure I was okay. The next day my period came. I started last Wednesday. Today is Wednesday night. I have white discharge, which is normal for me, but it had some brownish, kid of reddish but not really color in it. I have been spotting since Monday. Do you think I am pregnant??? Or is this normal?? I keep freaking out :( I'm 18.