Hemorrhoids are relatively common during pregnancy. Some women get them for the first time while they're pregnant.they often go away on their own
Probably hemorrhoids, but if it perisits, I would contact your Dr. just to verify that's what it is.
If it is a significant amount of blood, I would contact your doctor. But if it isn't very much then I would suggest that it would be hemmroids. You can try Tucks pads, Witch hazel pads, or a cream like preperation H to help with the hemmroids, unless they are internal.
Drink lots of water, and make sure to get a lot of fiber.