My guess is your transmission linkage became disconnected. I had this happen at a Walgreens store. I had to have the car towed home. A linkage pin retainer had come off.....easy enough to fix.I was driving my E320 model 1995 and I stoped, When I returned back to the car to go for a drive again, the car will go into any gear including D but it won't move. It is like every single gear is neutral !