Fleas?

Well Bella has been scratching recently-a lot. We took her to the vet, and they dipped her, but she is still itching. They said they found 1-2 fleas, so I don't know if I necessarily believed them. I try to check her fur, and I do find one little bug walking on her, but I don't know if its a flea because I thought fleas jump. We used the flea comb on her too, and found nothing. She is on frontline plus, but I was reading that it doesn't work, especially in florida. She has these little scabs all over her. Originally we thought it was from the cats because they were only on her back. Now we see them on her chin and belly too. The vet said it was normal, which I find hard to believe-so I am going to start looking for a new vet. I have cats too, and I don't see them itching or licking more. I am going to start them on a flea medicine soon, and I am going to bathe them and treat their sleeping areas (vacuum and hot water). So do these sound like fleas, or just some other bug. Is there any treatment that is better, or something that I can do to nip this in the bug.