Curious question

Ok so I have a question. I had my period The 7,8,&9 of this month. My period was kinda normal but it's kinda hard to say because they vary on flow each month. My boyfriend n I have had sex twice the weak after. One we used a condom. Other was pull out method. We have also done the pull out method all the other time we have had sex. Then last night I started cramping and I spotted real lightly for about an hour.  So my question is why Is it I would do that?  I have never spotted like this before.  Could it that I might be pregent?  I ask this because when I got pregnant with my daughter I found out about a weak n half or 2weaks after I had my period.