About over a week ago I saw a small amount of red blood on toliet paper after going to the bathroom. I also had some pain and anal itching. There hasn't been any blood since then but I seem to have some gas and a weird feeling in my behind (kind of like a full feeling). There is also some pain. Does this sound like it could be hemmhroids? I am worried about more serious things such as colon cancer even though I am in my early 20s.