Odds are that it could be a cold, if that's the case she might need some antibiotics.
Sometimes the colds go away on their own, but other times, when the cold is hanging on for a long time, they need the antibiotics.

I would take her in and get her looked at. Talk to a few vets first, and see if they will set up a payment plan with you, so you can afford it over time. Hope this helps, good luck.