Thanks.
The vet called back and said that if it is a case of poisoning from pesticide that it's too late to administer anything like charcoal and that the main thing she needs now is fluids. She told me to give her water by syringe into her mouth, just a bit at a time, every half hour or so. (about 20 mls before we go to bed). If she manages to keep it down then I'm supposed to offer some food tomorrow, either bland chicken or chicken baby food. If she does start throwing up, she wants me to bring her in and they will put her on fluids.
I'll post an update tomorrow.