Usually a hemorroid will cause this. Do you notice the bleeding after an episode of constipation?
Whwn blood is bright red that usually means it's "fresh" blood. Could be hemroids but you should never mess with rectal bleeding. A very simple test can be done in a Dr.s office to tell.
It could be an internal hemorrhoid.
it could be piles which is quite common.if it carries on for a long time, go and see the dr to get it checked.im sure its nothing to worry about. keep smiling :-)