Why did my Electrolux Ambassador Vacuum stop running?

My Electrolux Ambassador vacuum cleaner stopped running when the dirt bag was full. I noticed that dirt sputtered out of the carpet attachment while I was using it. The attachment continued to work even when the canister wasn't. I changed the bag as well as the filter bag, but when I turned the vacuum cleaner on again it did not work. Did the motor burn out? I hope not. It's too expensive to replace the machine. Hope I can get an answer ASAP. My house really needs a cleaning! Thanks.
Nina