why does shawn michaels act like this?

[HBK= #1]

ever since he got injured by randy orton he hasnt been the same shawn michaels.his looks have changed (he looks alot older with that beard) his actions have changed (like his entrances and his matches).he just doesnt act like the showstopper no more.i mean he hasnt won a match with sweet chin music in like a month (wich isnt bad).and he always faces little superstars like lance cade mr kennedy people like that and he looses.when before he would face people like john cena batista triple h and he would win.i just dont get it.
its not cuz hes too old.look at wrestlemania 23 he was the same age then and look at that match