While my car was in motion (under 5 mph I think) I put my car in reverse. Normally me and my parents always do that and nothing happens but just now when I did it, the car short stopped before I reversed and it never does that. Now every time I put the car in reverse, I feel the car shake but it still has no problems reversing. I don't want this to give issues in the long run. Do you think I messed up the engine? No strange things happen when I put the car on drive. What do I do?