Congrats to your son, kiddo. This does sound like the perfect fit from how you've described the entire situation. AND, with how quickly it all happened, the fact they want him permanently right away instead of temporarily...sounds like son's HP was leading right to the job meant for him!
As for you...I'm sure whatever you decide to do next will be perfect for you too...seeing as you are so aware of who you are and what you want. Recovery...it's just like dominoes!!!