So happy to hear you found him!!! Truly is nothing short of a miracle!! Keep a close eye on him, not sure if you had the chilly nights we've had recently, but he might be prone to a mild cold / respiratory problem, nothing serious if you notice it right away! Don't want seem like I'm being overly worrisome, but its a shock to the system, and that can open the door. If you notice or hear anything funny coming from him, get him to the vet as soon as you can.
But, I am so very happy for you and don't kick yourself in the pants too much, these little ones can be so quick... accidents happen, just be thankful he's back home and safe!!!