2004 Chevrolet Cavalier Car Automatic Transaxle Suddenly Gears Work Had Engage

The car is automatic transaxle and suddenly none of the gears work. I had to engage the emergency brake to keep the car from rolling backward (driveway is slightly uphill). I was driving the car with no problems or warning lights and as soon as I pulled in the driveway and put the car in park, the shift lever seemed looser than normal. Now the car won't start although when I turn the key, the dashboard lights come on. Does this sound as though the transmission is gone?