Ever seen a toddler discharge something from ?

My 17 month old son was sick with the flu all last week, come saturday he seemed better as far as the diarrhea was concerned but started discharging something obviously painful from his . He wasnt peeing because his diapers werent wet but he would cry and grab himself down there and when I would open his diaper there would be brownish orange droplets in the front. so I got scared and took him to the ER where the MD said there was nothing wrong, he wasnt dehydrated, and has no blood in the urine , no UTI or anything and promptly sent us home with orders to push clear gatorade for the next few days, he is now fine and peeing great, any ideas of what that may have been?