The good news is everyone is OK. DO NOT WORRY.
After school, Carter wanted to go to the playground "by the house" so we hopped on the bike with trail-a-bike and took the back road and had a great bit of pretend play at the playground. Mostly it involed us going to get ice cream, and Carter was the ice cream man in his shop.

"I know what you want, dada, because I'm the ice cream man." Who knew all I needed was an ice cream man to tell what I really want....
Apparently, however, what I wanted was strawberry cake and I ate it all in one bite and didn't share. After getting a second, smaller cake for Carter from the ice cream man (because "my mouth is small so I can't eat a big cake") we drove it home "CAREFULLY" in our car below.

At various points in the adventure there was a pizza man, an ice cream truck, some boxes, a house, and a car shop where I received several free cars (all new cars, of course). Suffice it to say, we had a great adventure and even managed to get in some good swinging as well.
Finally we headed home on the bike and all was well (though the hills are really hard with an extra 70ish pound trailing behind-Carter plus the all steel trail-a-bike). We pushed up the final hill and pull into the driveway. Just as we turn, one of the cars stopped at the light by our house says hi and we realize it is a friend of ours who has a daughter that is a good friend of Carter's. Well, I looked over my left shoulder to say hi, having just unclipped my right foot from the pedal. Suffice it to say my weight went left, so did the bike, trail-a-bike, me, and Carter, while my left foot stayed safely and uselessly clipped into the pedal. All, right in our driveway, right in front of our friend and all the other traffic at the stop light. Carter hopped right up, helmet on, not a scrape to be seen. I hobbled up, helmet on, feeling more stupid than usual, but no scrapes either. Thankfully, our friend will likely tell his wife what happened, who will tell her good friend Elizabeth, so I won't have to break the news to her!
Carter didn't even seem to realize anything strange had happened, so I am confident he won't mind getting back on the bike with me!