Your Sasha is a beautiful little girl. So sorry you are having issues. Definitely get a 2nd opinion and education yourself as much as possible on toy breeds. Caring for one is very different from other dogs. If you vet isn't very familiar with toy breeds, I would look immediately for a new one.
As far as her sneezing/coughing fits, if she was vaccinated (regularly or intranasally) for bordetalla, it is possible she actually contracted kennel cough from the vaccine.
Please review the attached vaccination recommendation by Dr. Jean Dodds, DVM that has been adopted by the top 27 vet schools in the US. Toy breeds have a very high incidence of reactions to vaccines as the amount given is intended for a much larger dog. They also have a very high chance of reaction when a combination vaccine is given. They should not receive more than one vaccine at a time, spaced out at least two weeks apart. Keep in mind that you can always refuse your vet's recommendation of vaccinations. My personal feeling is this schedule by Dr. Dodds is the way to go.
Vaccination Schedule Recommendations For Dogs
Hope this helps and that your babies blood work is normal. And welcome to YT!!!!!!