My lab puppy is vomiting and won't eat?

[Carselowey34]

I have a 6 month old lab puppy, we are not her first owners. She is unfortunately one of those puppies that eats just about anything. About a week ago she got on our counter and ate 10 donuts. I knew she would be sick so when her stool became soft I wasn't too concerned as she was acting as she normally does. Two days ago I became concerned because before I went to work (Friday)she was very lethargic(unusual for my bouncy puppy) and she had thrown up during the night, when I came home she was even more lethargic and it didn't appear that she'd eaten anything. I am a paranoid dog mom so I convinced my vet to work us into the office, and he pushed on her stomach and looked her over and didn't believe she had a foreign object in her body. We left with a prescription for the diarrhea and instructions to feed her a bland diet of boiled chicken and white rice. It is now Sunday and I am just about to work myself into a frenzy, she has no interest in getting up for anything other than the bathroom and has only eaten about 1 and a half chicken breasts which is unusual considering she is a good eater. My husband thinks we aren't giving the medication enough time to work, but I think there is something bigger than just a bacterial infection happening. She has a doctors appointment tomorrow after I get off work but so far today she hasn't eaten a thing she just drinks an enormous amount of water. Does anyone think this behavior warrants a trip to the emergency vet? I am hesitant to do it because I know it will be expensive but I am also terribly concerned that I'm not seeing improvement.
I have a tendency to be overly paranoid and assume the worst outcome so I thought it may benefit me to get an objective third parties opinion.
Thanks!