First off, thank-you for taking this dog in! I agree with you that she is for sure better off with you than on the streets, and I'm glad to hear that it seems that she's improving! That said, though, based on what you are describing, a vet visit is definitely in order, and the sooner the better.
Is the only/main reason you're unable to get her to a vet because of the money? Or is there another factor at play? If it's just the money, I'd look into Care Credit
. It's basically like a credit card but for medical expenses, veterinary care included, and most of the vets I've been to will accept it. From what I understand, they'll pay the veterinary costs up-front, and you just pay them back in monthly increments. If you think you'll have the money when you move back home, this might be a good option since you likely won't need to make a payment until you're back home anyway.
Another thing I'd consider is seeing if there are any "big-box" vets in your area. Many Petsmarts, for example, have a Banfield in them, and Banfield offers a coupon for a free first visit.
If you have a Banfield near you, this might be something you want to consider. If you truly have no money to spend, I'd just call them up beforehand to ensure that the visit itself is truly free. You'd obviously need to pay for any tests performed, treatments done, or medications prescribed, but if they confirm that the visit itself is free, you can always deny any/all of these things, and walk away without paying a penny. By taking her, though, you'd at least get a general idea of what it is exactly you're dealing with. Plus, the vet may be able to recommend some inexpensive products, or suggest some things you can do at home to help treat her.
I wish you guys all the best, and please keep us updated on her recovery!