My red devil acting strange

he is a little over a year, nothing has changed in his tank and i have mantained it regularly, and he is getting last couple of days extra agressive (he is by himself) but attacking the glass, heater and gravel a lot and he is starting to get bright red, but his abnormal behavior is he is hovering round the top and not moving as much, is this normal

That's fairly normal for aggressive cichlids as they mature. Certainly not all develop these behaviors, but many will.

MM