What Causes Vaginal Spotting And Stomach Cramping?

I had my period 2 weeks ago, and when I wiped earlier today, there was slight blood on the toilet paper. (looked like little veins, to be precise) Then right after I ate today, my right side right under my stomach started to hurt, as if I was having cramps. I don t think this has anything to do with possibly being pregnant, I just want to know why this is happening.