Just went for my first day riding outside instead of the trainer yesterday. It's the middle of winter here but we got a few days of less than freezing weather and the snow was all gone.

What was left was all the little rocks they put to keep people from sliding on ice when it's too cold for salt to have any melting effect.

I got a few of those rocks in my rear tire. Is it normal and not a problem or will I get a flat tire/have to change tire if I keep rolling before than clean the streets in spring?