Keep an eye on him, which I'm sure you're doing. Monitor his temp which should give you an idea of his progress, and I'd say if things don't seem to be going as you'd like, take him in for medical care at your family pediatrician or ER. Good luck-I hope he's better soon. As well, if this is his first flu, which is what you believe it is, then perhaps a trip to the Doc or ER is a wise thing. If he's older and the flu's no stranger to him, just keep an eye on him. Again hope he's well soon, and you're at ease.