Stomach Bug?

I’m not sure what’s going on with my 18 month old. He started on Monday night complaining and crying in his sleep. Woke up a vomitted. Just once. Then next day seemed okay. After lunch he was crying like his stomach hurt. Laying curled over. Took him to see pediatrician. Wasn’t very helpful. Just told me it’s viral. Keep him hydrated and give him Tylenol for pain and gas drops. He is not contipated. He has no fever. He is staying hydrated and eating ( alittle less then normal). It just seems like the stomach pain. Anyone been going through this? Also no changes in food or diet. No one is sick at home. He did the same thing today after lunch. Went down from his nap and woke up crying and rolling over in pain. Just got him to calm down.