OK....spoke with the asst. principal this morning.
Sure enough, this is why she was calling. She asked if my son had said anything and I told her what I posted earlier that he said happened. She said that he was pretty accurate in what he told us last night, with a couple of additions.
The teacher left half day yesterday and they had a substitute (red flag number one). My son has severe constipation as a result of his diet and medications; so when he's gotta go, HE'S GOTTA GO! The little girl said that he forgot to turn the go sign to a stop sign and she went in by accident. Then she was upset I guess because my son was taking a long time (see above constipation comment). She "took his picture". I guess she also had the door swung wide open and the teacher saw it...it also means that the whole class must have seen my son (which DOES bother me more than I was bothered yesterday...kids tease). The substitute put the girl immediately on yellow. I guess the little girl flipped out and was super upset so they called the assistant principal over to help calm HER down. The asst. principal heard what happened and personally checked to make sure the camera (which belongs to another little boy in the class) was fake. She showed my son the camera and tried to reassure him it was fake (for when he told us what happened).
I ended up talking to her for a very long time. She was great and I'd never spoken to her before. I told her that we had spoken to my son the night before. I told her that I wanted her to know that my husband and I understand that kids will be kids and we wanted her to reassure the little girl's parents that we are NOT super upset and we are NOT going to turn this into some hugely big deal. The fact that she knows it was wrong is enough. The assistant principal was very appreciative and said that she was a little surprised at how well we were all taking it because most of "her parents" would be freaking out. She said she'd react like we were and she really was glad that we could look at the situation with perspective.
It does not sound like the girl got suspended, but they definitely addressed the issue. I am totally satisfied with the way it was handled.