The doggie equivilent of the terrible twos. :D
I am glad Harley is doing better, but I would also put him on the NILIF program that Micki mentioned for a while. The fact that he growled at you AT ALL deserves it. It may very well have been the stress of redecorating your room, but do you want him to act like this everytime anything in your life changes?
Do not think of it as punishment. Status seeking dogs live happier lives when they realize that they do not have to control everything. ;)