Some cats have that reaction to anesthetic. Of all the males I have had done probably three of them reacted like that. A couple of the girls did too. They will eventually settle and get their rest. Just seems like they have to get it out of their system. If you are really concerned give your vet a quick call.
As the others said, keep him as quiet as possible with no jumping. I'm sure he will be good.
Assumptions do nothing but make an ass out of u and me.
We can stick our heads in the sand for only so long before it starts choking us. Face it folks. The pet population is bad ALL OVER THE WORLD!