Hmmm, he`s obviously changed behaviour for some reason. Sometimes older hamsters can become excitable for some reason. I saw this with two of my robos who sadly, were only a few days away from passing.
But one had a very bad skin condition and had seen the vet a week earlier and the other went much the same way, although he also had a spinning disorder too, poor love.
Keep a close eye on him and if he settles down again, that`s good. Sometimes they crave more attention though so I he wants out to be with you, try and be there for him. x