My dog threw up yesterday, and today she made a wierd breathing sound twice, and had diarrhea once.?

shes a 3 1/2 month old puppy, (chihuahua mix) she eats normal hard dog food, she takes walks sometimes, but not today because of that sound, shes been a bit lazy, im gonna take her to the vet soon, til then, what do u guys think is wrong with her? :'(