I'm torn about what to do about my poor pup.
By way of background, Molly caught kennel cough at the shelter. It progressed into pneumonia. We got two antibiotics, plus one for diarrhea. Eventually she was throwing up and having diarrhea so much that we took her to the animal ER. She was admitted for 3 days for IV fluids or antibiotics. They found out she had hookworm and dewormed her, transitioned her to oral antibiotics, and gave her fluids until she was less dehydrated. They also did an ultrasound and saw that her uterine stump (what was left after her spay surgery) was inflamed, but her surgery had only been a week before, and she wasn't in any pain, so they said it probably wasn't anything unusual or to be concerned about.
She made an amazing turnaround. She had so much more energy, her diarrhea and vomiting vanished, and so did her cough. Her appetite was amazing and she managed to put on 8 lbs in 2 weeks.
Then yesterday she started having a really scary new symptom seemingly out of the blue. Sometime yesterday afternoon she started breathing REALLY heavy. Just like really rapid, shallow breaths, all the time. Sometimes with her mouth open, but a lot of time with it closed. Not exactly panting. Just really heavy breathing. She couldn't sleep or rest, because every time she put her head down, it was too hard to breathe.
We took her back to the pet ER at like 11:30 last night. There was only one doctor and she was spread super thin, so I don't think she really gave us the attention she should have. She took Molly's vitals and said they were all normal. She said that it was really humid out (it is, the most humid it's been since we got her) and that Molly was probably having trouble cooling off, so she was panting excessively. I was honestly really exhausted and anxious to get her home, so I just accepted that explanation, even though I really don't think what she's doing is exactly panting. She told us to run the AC a little cooler, get a dehumidifier, and she'd be better in a day or so.
Fast forward to now. Ran the AC at 66 degrees all night. Bought a dehumidifier as soon as Target opened this morning. No improvement. If anything, she may be worse.
What would you do? Go back to the vet ER? Go to the regular vet first thing tomorrow? Just wait it out and see if it gets better on its own? Any ideas about what could be wrong? The google has been really unhelpful, most info is specifically about heavy panting, not heavy breathing, and even the stuff on breathing is super vague and unhelpful.