What's gotten into my clowns?!

So i have 2 ocellaris clowns in my tank. They have this rock that they spend most of their time around. they clean it it constantly and are always guarding it. Whenever i'd put my hand near it to clean the algae or anything they would sort of swim around me and i mean, i could understand they were protecting their territory. Lately they've become much more aggressive. I can't stick my hand ANYWHERE in the tank without them instantly attacking my hand, and i mean ATTACKING. slamming into with a significant amount of force. they do the same thing to the algae brush as i'm cleaning the tank. What has gotten into them?

 

are they adult size? ususally clownfish are very territorial to begin with.. but it possibly could mean they are about to start breeding or have already laid eggs.. check the different rocks around that area and see if you find some eggs.. if they are not adult size and are not breeding, probably just a pair of very territorial clowns

 

I don't think the clowns are sexually mature yet because they're still pretty small. i mean the bigger one is probably 1.5 inches which is why i cancelled out the possibility of them laying eggs. but what else would make them randomly become so territorial of the entire tank.