Help me

My son is 11 months old. He's always seemed to be a "puker" since I can remember. He's gained weight appropriately and the doctors have never had any concerns but the past couple months I've noticed he's started puking more regularly. It seems he throws up every morning after his first bottle. He was drinking six ounces but we have cut it down to 2-3oz bottles 30 minutes apart to see if maybe it helps but it has not. He drinks them fairly quickly but he is still using the slow flow nipple to try to help control it. We burp him like normal. I don't know what to do. He throws up every day sometimes a couple times a day. Could it maybe be a reflux problem? He never seems to be in pain from it but it has us almost confined to our house 24/7. I want answers. He drinks enfamil formula, regular yellow container and he still nurses.