Heater blowing cold air. Temp gauge at hot. Drove car 6 miles before I stopped. Missing clamp for upper radiator hose. How long will it take to know if damage happened
It is very likely damaged right now. Take it to a mechanic to confirm.
Modern engines do not take well to being run without coolant.
Sincere good luck with the mechanic’s diagnosis.
You stopped the car after 6 miles, or the engine stalled. Big difference. If the first you may still be in luck. If the second, the engine may have seized which means it is finished.
The worst always shows up right away. The less than worst takes a little longer