Oh no I appreciated the advice.
She is eating when I cook her salmon, and appears to be OK otherwise aside from being thin and the odd shorter/more rapid breathing. In fact she ate an entire pack of bologna today fed to her one at a time.

No hacking today at all. The breathing is a bit unsettling to watch, she does pant open mouthed occasionally....with the odd diaphragm movement although I have no idea at what point its 'distress'. To take her in to emergency would be around $40/hour, and I'm out of work currently. Really not out to rack up thousands in ER bills if she can make it to her Tuesday appointment.

Here's her today:
https://vimeo.com/214346878

Could the pain from the tooth cause breathing like this?
Asthma?

Hi. Nothing I see makes me think that the tooth has anything to do with your dog's situation. If I were your vet, I would be focused on what is going on in the chest. An X-ray would be the best diagnostic tool, other than a good, thorough physical exam. Good luck.

Thanks folks for your comments. Roo passed away early Sunday morning
She seemed to be a little better breathing and even her appetite had come back as I said.
But then she was up all night and unable to lie down, and her breathing got worse, then better, then worse.
About 3am I finally got up and got ready in case we had to go to the 24 hour emergency clinic. I was hoping she could at least get through till sunrise so we could find a vet open on Sunday, and beg to get her bumped in. I had talked to another vet, Chatham Vet Clinic Saturday and they had said they were booked through May, and she already had her appointment Tuesday which everyone kept saying was "not far off".

While I was online searching for vets she came over to my chair looking up at me with her neck stretched out oddly breathing heavy, imploring for help, and collapsed on the floor. I managed to get her in the car which was difficult as she apparently couldn't sit down and breathe and ran her to emergency. They got her on oxygen and she was scared, but breathing better.

We did an x-ray at the clinic and found her lungs were about 75% full of fluid. They gave me so many possiblities the test seemed almost useless from a decision standpoint... including cancer and bacterial infection but to me it looked like heart failure. They said they could drain the fluid but it would likely come back. The potential bills they quoted were astronomical, she would need to be on 'life support' thru Monday before they could even begin.... and with her being 14 or 15 years old and the trauma of a long uncertain battle we finally agreed that euthanization was the only humane option.

All she wanted that last morning was to breathe, and to be with me :/
Roo, I could never say how many times over so many long years you made me laugh and smile... how simple were your wants and how much joy you gave.
I'm so sorry for your suffering, and that I couldn't save you.
I left you that morning because I couldn't bear to watch you go to sleep but please know you never left my heart. My little Roo.

So very sorry.

Run free, Roo xx

So sorry for your loss.

So very sorry to read this. Run free Roo x.