Yes, I think you made the right move. He might be physically and intellectually mature enough, but he hasn't got that emotional piece of the puzzle yet. Pottying is a developmental step that kids make willingly, often even eagerly, when they are truly ready on all levels.
But your son is signaling the expectations have him feeling really uncomfortable, and his anxieties ("Do I really have to behave like a big boy ALL THE TIME?") have caused some regression.
I'd be really, really nonchalant about the potty issues for a week or so, simply telling him that you are confident he'll use the potty when he's ready. Then give it some time to sink in that HE'S in control. He will ultimately have to be anyway in order to be fully trained.
Moms who have been working hard on training feel real discouragement when they hit this VERY common wall. But your child just needs more time to sort it out. I've known a number of moms who have put their child back in diapers, expecting their children to never get trained. But once the kids know they get to advance when ready, they do. Sometimes this is only a couple of weeks, or a couple of months, later. Then they are trained – often in a day, or a week, with fewer accidents every day. It's their decision, and they go at it with enthusiasm and determination.
So try just cooling it for a while. If at some point it feels welcome, go back to reading occasional potty books, watching a video here or there, having pretend potty parties with his toys modeling how to get to the bathroom like a superhero, or whatever his favorite images are.
Lots of kids don't fully train until three or later. Boys tend to take longer than girls, and sometimes they are four or older. But pushing while he's balking will not speed the process, and is very likely to slow it down.
Here's a request on this site where several moms told of the success that followed giving their children freedom to make this decision: http://www.mamapedia.com/questions/6651391040949452801#re...