My sons did that. Just put some alcohol around it and clean it up and try not to have anything hit it! And like @mommy99630 said..if it doesn't stop or looks worse go to doctor!
I used peroxide to clean it but if it doesn't stop bleeding you have to take your baby to the doctor
Make sure you clean it with alcohol every diaper change and keep it out of your little ones reach , if it continues to bleed , like immediately after cleaning , call your doctor