That's right. "Look out dumbass!"

I got yelled by a driver "Watch where you're walking! 😡" when I was depressed and walking alone to school and crossing a low-traffic street...

Yea I kinda felt even more depressed that day...

It depends on tone of voice. It can be said gently and by someone overseeing care. Tension reveals if their is a mismatch between the stumbler amd the speakers assumptions about the speakers rights to give imperatives. Some people dislike any form of governance, evem gentle care, and in that case, even kind of warning will always set them off, in any context.

It is about what we assume and imply about ourselves and others.

Every single time, my brain goes “no! Now I’m going to maim myself out of spite,” and then I feel like an asshole for (internally) responding like that to someone trying to help

I think it's often a short hand to get people to slow down and pay attention. Be careful! Take it slow, no rush.

I find being told to "be careful" irrationally irritating, especially when I'm on foot or on my bike and I'm told to "be very careful" before going on a road. Like, of course, if nobody told me I would have let a car hit me. Or if one hits me, it's because I wasn't careful enough.

I understand what people mean when they say that before going on the road, but every time my brain is just like "ok, but some it I can't control".

Does anyone else here kick the rock they tripped over?

"oh are you ok?" Is what prefer because of that. Unless there is concern there are more hazards right ahead