Thanks for the additional information. I really appreciate it.
Obviously it's hard to know for sure what's going on, however, if it looks more like the first clip, then it could very well be that she's got something called tracheal collapse...which is actually pretty common in small dogs. I have a maltese cross who has it and has an attack a couple times a week for years with no problems.
This can be a chronic, degenerative issue that could impact the health of the dog. You can find more information on this particular issue here( and although this is an article about small breeds, there are large breeds with this issue as well): http://www.toybreeds.com/health.htm
The other thing I was thinking was the possibility of this being some kind of cardiac cough. Dogs get congestive heart failure (also known as CHF) just like humans. This is when the heart doesn't pump as effectively as it should, which causes fluid to build up in the lungs, making the dog cough. Since you said it looks like the first video, I feel pretty confident that it's not CHF, but it bears mentioning anyway...just to be safe.
Tracheal collapse is normally treated with a cough suppressant and steroids, and sometimes the vet will opt to do nothing unless it starts having an impact on the health of the dog.
There's another good site that goes over treatment options here:
I understand that you(like so many other people) are in a hard financial spot right now. There are some organizations that might be able to help. If you'll follow these links: http://www.speakingforspot.com/helppayingforveterinarycare.html , http://www.theamericandogmag.com/non-profit/resources-veterinary-bills-financial-assistance, you'll find dozens and dozens of organizations that may be able to help pay for you to take your dog to the vet. Also, there are some clinics who offer free exams and other treatments and require that you only pay for medications. If you'll follow this link: http://www.vcahospitals.com/main/offer , you can see if there is one in your area.
I hope this helps!!