A few minutes ago Luke and I were playing ball in the house as we normally do during the day. Sometimes he gets a little excited with the ball while playing with it and growls at it while tumbling around on the floor with the ball. It's no big deal, I just stand back and let him play. But this time as I was turning to walk away, he barked at me. I turned back around and he was crouched down low in a lunging position, growling at me! I knew no good could come from that posturing so I turned back around and walked away slowly. He then raced past me and swung around in front of me and crouched down again and growled. This time he didn't give me a chance to turn away before he lunged at me and snapped at me. Then he ran away again at top speed, swung around behind me jumped up and bit me again. I screeched "ouch!" and stood still with my arms folded, turned away from him again and he ran back up to me, growling and bit me on my knee! He kept hopping up and biting me no matter how many times I "yelped" until I finally had enough.
Whenever he does this to the kids, i put him on a leash so that I can control his movements and access to the kids. It seems to calm him down. So I put him on a leash. He went to sleep immediately. He has never done this to me when the kids weren't around. I don't understand what happened. He was fine and then all of a sudden he went nuts!
Can anyone shed some light on what might have happened and I how I can prevent something like this from happening again?