Worst. Feeling. Ever.

Ugh...I did it, I left my child screaming and crying at school "Mooooommmmmmyyyyyy". Completely. Sucks. Not sure what is going on but on Tuesday we had a biting incident. The biter being Dane. I am in no way saying that he's innocent, he's not at all and he does have a tendency to be a bully. However, biting isn't usually his thing. The child he bit attempted to bite 3 kids when I was the room mom the previous Thursday. I am not sure what happened, the teacher and the room mom just saw Dane biting but don't know what happened to cause it. So...this morning he was all ready for school and excited. As soon as we walked into his classroom, he walked right over to the child he bit on Tuesday and shoved him to the floor. What the?!?! I grabbed him roughly and scolded him and the tears started. That is when he started saying he wanted to go home and didn't want to stay at school. The teacher said she wasn't aware of anything happening between the two of them or why Dane would be targeting this kid. Why does he despise this kid so much? I can say that this child seemed to be the problem child when I was in the class last Thursday, however I am afraid my child is now filling those shoes. We scold, we do time outs and we spank....what did you all do to correct a bully? Especially biting? I can deal with the pushing and hitting and chalk that up to him being 2, but the biting?!?! It's so vicious and I thought he was past the age where that would be a problem. Comments and / or advice welcome!