Whose kid is this?

We attended a Valentine's party at Luke's preschool this week. All of the children exchanged valentines (which the mothers had selected and assembled, of course). They were supposed to sit in a circle and sing a little song. Each child had a construction paper heart to hand to their mother, as well. Guess who's little boy refused to sit in the circle? This is the same circle that he sits in every time he is at pre-school. He was extremely stubborn and insisted on sitting apart from the circle on a stool. He was happy to hand me the heart, along with a big hug and a sloppy kiss. It still didn't win any points. I am so FRUSTRATED with this child! Each time I pick him up from preschool or MOPS, I receive a discipline report from the teacher. The yelling and the talking back is probably par for the course right now, but the disrespect for authority and the hitting and kicking other children is becoming a bit disturbing. It's like he's two personalities: the sweet, articulate, enjoyable little boy who usually lives at our house and the obnoxious, disrespectful out-of-control little boy who arrives occasionally and mortifies his mother. We took him to the pediatrician yesterday for a little discussion. The doctor referred us to the behavioral health department of his practice. He said we aren't presenting a situation that sounds like any kind of personality disorder, but since we are concerned then he wants to refer us. The part that just makes me laugh is that the first available appointment isn't until the end of April. Looks like we could be in for an eventful spring around here.