I know this will be a little difficult to do think there is anyway to get a feel of her belly? If that is possible you should be able to feel if there are still kittens inside. But you must be very gentle as her tummy maybe sore. Also is there any shelters near by you that has a vet on duty? If so maybe they could do the exam for you and it won't cost anything or it will cost very little. Just some suggestions that may help.