Panic?

This is a strange one. The driver veers into the bike lane almost putting me onto the pavement. When I shout, he pulls ahead and then, bizarrely, pulls right in to the left (with a late use of the indicator) blocking the bike lane completely. I moved out to go around him, letting him know I wasn't happy, but TBF I did hear a "Sorry" as I passed. He then proceeds to pull back out into the traffic and goes on his way. It was all a bit puzzling but I can only guess that he panicked a bit, pulled over to either apologise and/or let me past and then got his act together. He didn't acknowledge me at all when he passed me again or later at some lights when I re-overtook him.