Accidentally "ground" my engine... Is it ok?

Hey! A week ago I got a remote car starter, and while the starter and the car are running fine I realize I've made a (potentially) horrible mistake.

When I was first shown how to use the starter, I was told that once the car started, I could put my key in one of two ways: either 1.) step on the brake, the car will shut off, and I put my key back in and turn it on normally, or 2.) put my key in the ignition and turn it on normally in which case the key will take over and I can drive.

However, by "turn it on normally" I assumed this meant turn my key all the way and restart the engine. The first few times I did this, the engine was started, I put my key in, twisted it all the way, then the car "shut off" for a second and turned back on. I assumed it was supposed to do that. Then a few later times I would put the key in, twist it all the way, and the engine would start to grind. I immediately realized that the sound was an indication that something was wrong, and after a little research found out that I'm not supposed to "restart" the engine... I just need to put my key in and turn it once, without twisting it all the way.

My question is: is it possible that I could have already damaged the engine by doing this? The car seems to be running fine at the moment. As long as I STOP twisting it all the way and continue doing it the right way, will the engine be OK or is grinding the engine something that causes immediate damage?