My son is 21mo and I believe he has the stomach flu. He's had it a little over 24hrs. He hasnt puked but he has diarrhea really bad. I've gone through 18-22 diapers since 7 last night. I've been giving him water and Gatorade. He's lethargic. I can't get ahold of his pedi :/ should I take him to the er and be looked at or just keep giving him fluids. He's never been dehydrated before so idk what's safe or unsafe. Thank you!