How long til a call goes through?

I was not supposed to call someone and I accidentally hit the call button whilst going through old text messages (stupid iPhones)
I hit end call IMMEDIATELY when the option was available. Did the call even register? How long does it usually take?

Your fine. Trust me when I say it didn't go through.

It takes a couple seconds for it to hit the tower, process and go to another. It depends on the distance you are from the tower and signal strength and amount of traffic on that tower.