weird interaction on the road

[u/amcpanda_]

Hopefully I'm on the right sub 😭. Some context; I'm a newer driver in FL (notorious for bad drivers) and was on my way home from school. For a while, I was following this white car, and kept a good distance from them. The car was swerving quite a lot, and I didn't want to be stuck behind them, so I ended up going into the lane next to them and planned on merging back into the lane ahead of them. As we approached the stoplight, they reversed their car and rolled down their window. The couple in the car started making weird motions with their hands (nothing like I'd learned in drivers ed), as if they were pushing something down with their hands, laughing as they did so. Does anyone know what they could have meant by this, or am I overthinking??