First of all calm down, it is not necessary that it has to be a cancer. Obviously, if you think this is a serious condition, you should go see a doctor, the more you delay, chances of getting the condition worse increases. Blood in stool could be because of other causes too but you will have to talk to a doctor in person and let them take your medical history in detail, evaluate you physically, to come to a conclusion. Please don't jump to any conclusions all by yourself or reading some random articles on web, it will only cause you anxiety. Stay positive, see a doctor and get the necessary tests done.
Next Steps
see a gastroenterologist