It could be a bit of cystitis? If it is, it needs treating to make sure it doesn't back up to the kidneys. Cystitis can cause a lot of urination problems, but is not terribly serious as long as it's stopped in its tracks. Usually it's easily got rid of, a short course of antibiotics usually gets it. Because in a dog, where the urine comes out, and the vagina are together, if there's an infection it will affect both. Hope it's gone soon...
Unfortunately, you won't know for sure that an infection is present unless you bite the bullet (or wallet in this case) and take her to a vet. With the added symptom of loss of bladder control, it appears to be a safe assumption that something is wrong and she needs treatment. It will only be more expensive letting a medical condition go untreated, so you'll actually save money by acting sooner rather than later.
Please post back and let us know how she's doing. Hopefully it's something fairly minor - and inexpensive. :-)