My son is messing with me!

I just got a call for the day care because he has been sick they said he threw up twice!! So I raced down to get him, really worried cuz when i dropped him off this morning her was perfectly fine. so I get there and he's sleeping so I carry him to the car and drive home all the while he is still sleeping. when i get him from the car he wakes up and giggles at me. I get him inside and he is FINE no temp, not tired or lathagic(sp?) nothing he is happily playing on the floor in front of me lol. he musn't have wanted to go to day care today  .
obviously i'm going to keep my eye on him but he looks great maybe it was something he ate or something.I dunno oh well I have the day alone with my boy anyway