My 2000 Echo is spitting gas at the pump

Has this happened to anyone else…whenI try to fill my 2000 Toyota Echo with gas it spits a bit back out at me and it will not fill as quickly as it used to. Actually you can only fill it in tiny increments and if you get the pump going too fast it simply shuts off. Does anyone know what the problem might be? I am just about to take it in for inspection and I’d liek to know before I go what level of problem I might be dealing with. Thanks.