Possibly, but he's been getting more fidgety over the past year, if you compare videos in the middle of last year with this one you can see he's losing control.
I highly doubt that would happen without putin's approval, and if it did happen without his approval I think it's one of the very FEW things that might get them to grovel. (not holding my breath though)
Air raid alarms go off all the time, even if nothing is close. As for Biden visiting: I do definitely feel that he's much more involved with the rest of the world, and less of a twit than trumpetter.