Sick cat-help-help-help?

i took in a stray cat in she about a yr. old, i notice a little drool problem,it got worse.took to the vet had all her shots.tested negative for feline but has to be retested in 6 months, there was a foul odor in her mouth,so has teeth cleaned and mouth is also fine. had worms but took care of that also.blood work was fine. still waiting results of febar test. help,help! last time had vet said when she went to the bathroom her stool was disgustingly stinky.she ask me if she had been mousing and eating them. i can't find any evidence of this is house .looked in closets and under bed no eaten mouses i can see.but after she went to bathroom at vet she came home fine so i thought maybe it was out of her system.no such luck she is now drooling on both paws are soaked with spit and acts like she's in a daze,thought some one was poisoning her when she sneak outside but shes been in for week,and each time she has an episode she is worse then out of blue it disappears and comes back every couple days, the vet is also stumped, is there a vet out there with some answers or someone things they know because this is seriously becoming a big problem. i don't have alot of money for expensive tests, i spent a small fortune already and i might have to give her up which would break my heart,since i only wanted to help her.please if anyone has a clue please let me know and please don't email me stupid answers.this is a very serious to me.the only other thing i can think of is seizures, i need some really good advice.i'm about ready to drop her off at the vet and tell them to figure it out because its really making me mad that they don't know. p.s.i take her to ban-field in the pet smart store are they good vets or should find another one i just can't believe they don't know,oh ,yeah when she gets these episodes she can't even walk Straight,help!