Does this happen every time? If so, see a doctor. If not, you COULD wait and see if it returns or gets worse. If you see a doctor, he may find hemoroids or a fissure; these are not necessarily serious and may only require that you "keep things really clean [wet wipes, for example] in future. IF you see a doctor and he DOES recommend a colonoscopy, by all means get it. I've had one (usually one per life time is all that needs to be done to see if your colon is normal) and I would far rather have had that than the treatment needed for colon cancer. No joking here; if you need one, get one.