Blood comes out when I take a number 2, what does it mean?

It started that only a little was coming out, it only stayed on the paper, now a lot came out, I saw a little red in the toilet water, and yesterday, or the day before, I started to have little cramps in my lower stomach. And please don't say I'm on my period or anything, because cancer runs in my family(I know it's not hereditary, but most of my relatives have/had cancer), so I'm really scared.