Am I over feeding my baby?

My son is about to be 5 months old on the 5th and he still eats every 2.5 to 3 hours. He takes 6 oz at every bottle and will SCREAM if I don't feed him right when he's hungry. I'm scared that I'm over feeding him since it is suggested that babies get no more than 32 ounces in a day, but he will literally scream until he is hoarse and sore throated if I don't feed him right when he starts giving his cues. I'm hoping that because his nighttime feedings are further spaced out (approximately 4-4.5 hours apart) that he's not getting too much but I'm afraid for him. His doctor suggests that we don't put cereal in his bottle since he has reflux it could cause him to aspirate the thicker milk so I've been feeding it to him in a bowl the way it suggests on the box. I'm just not sure what to do. I don't want to do any harm by over feeding him, but he will give himself a sore throat by screaming if I don't feed him every three hours.