Going up a very, very steep hill

Today I went up one of the steepest streets I've seen. My friends and I were looking for a place to park. And at one of the streets, I made a right turn (wrong move) into this mighty steep incline. My friends were telling me to shift, but I didn't because I was too afraid to while the car was moving. I was on D the whole time, and it seemed like gravity was going to pull me down. The hill wasn't that high, but during those few seconds it seemed like it was. Well, my question and concern is did I put any stress on my engine or tranny climbing up the hill on D mode? I mean it was steep! Don't drive a manual up there!