Strange brake malfunction… or safety feature?

Hi community, I was driving in my 2013 Cooper S Convertible 6 spd that I haven’t had too long, in LA Tuesday night when it started getting insanely windy before the fired, and presumably because of some debris flying around, the cars in front of me stopped hard and so I jammed on the brakes just about as hard as I could. I can’t remember if I thought to engage the clutch or if I left it in gear, but when I went to go again, the car wouldn’t budge. It felt like the brakes were still engaged.

Now, I am in the lane next to HOV in the middle of a huge freeway during rush hour, so this is less than ideal. I turn the car off, start it again, same thing. I pump the brakes a bit, try again, nothing. Engage and disengage the handbrake, try 1st, try 2nd, nothing. Repeat various things, and eventually it starts to move a little bit in 2nd.

From there I’m able to get all the way right and off an exit in 2nd but it still feels like the brakes are on. I pull down a side street and it’s kinda loosening up.

I stop and pause for a second and breathe and take inventory. I’m thinking maybe I got something stuck under the car, or, I really don’t know. Everything seems normal.

I try again, and it goes. Perfectly normal.

What gives? Is this a safety feature that was engaged because it thought I got in an accident?

Thinking the Potenza RE71Rs and the weight of the convertible might’ve saved my car!