So, I have been working with Baloo heavily on recall. He is doing a good bit better and is starting to come to me when called, even when otherwise engaged. Except for today... Baloo has been becoming increasingly reactive with small dogs. Or at least, that's what I think it is. He will get over-amped up and start totally freaking out and trying to pounce on them to play. This has happened only a couple times, and I usually just leash him and take him to time out. Sometimes he will absolutely SCREAM at the end of the leash wanting to pounce on them. It's not aggression, he just wants to play, but he plays too rough. Well today, he was getting a little amped up, so I went to grab him and put him in time out. I put my hand on his butt and he turned around and bit me. Hard. And then snarled at me and scooted away. I didn't know how to react so I just clipped his leash and took him to time out like I'd planned. Now Baloo has always been a "mouther" so to speak, using his mouth a lot to communicate. When I clip his nails, he will keep his open mouth on me and squeeze a little when he gets stressed. When playing, he will nip at my hands and feet. When training, he will sometimes get a little excited and bite at me or grab me with his mouth. It's never enough to hurt and it's never serious. This is the only time he has ever bitten seriously and it hurt. I've never really had this issue before. So I don't even know where to begin.