Post spay urinary issues - HELP!

We've had Miss Bella for two weeks and she's 6 months old.  She was at a breeder who has been inspected by the AKC and passed all inspections.  She had all her shots with the exception of her rabies and is micro chipped. 

She would be 6 months old on June 10th so when I took her to get her rabies, I took her to Banfield and signed her up on their wellness program.  The vet recommended that she be spayed asap so that she didn't have her first season.  So we scheduled the surgery for June 8th.

She had her surgery and they sent her home the same day.  That's when the trouble started.  I had noticed on 6-7-09 that she was shaking her head & scratching her ears so I asked them to check her ears.  She has very hairy ear canals!  She has a yeast infection and a mild bacterial infection so they gave me ear cleaner & medication.  They also sent liquied pain medication home. 

1.  6-8-09:  She was sleeping in my bed with me and urinated without even knowing that she did.  It didn't stop there.  All week, she has urinated uncontrollably in her pet taxi.  I called the vet on the morning of 6-9-09 and they said that her urination without knowing was probably due to the anestetic and it would improve as she came out of it.

2.  She can't get enough water.  It's nothing for her to drink two cups of water at a time. 

3.  6-10-09:  I took her back to the vet and they examined her.  The surgeon said that her surgery went extremely well and there were no problems.  They couldn't get a urine sample so we went home.  The surgeon said to stop her pain meds and ear meds in case it was a reaction to one of those that was causing the problems with urinating without knowing.

4.  She threw up in the car on the way home and again at 11:30pm.   More urination in her taxi.  Not small amounts.  It's wet.  

4.  6-11-09:  We were actually able to catch a sample.  We took it to the vet and the surgeon said that no bacteria etc was found.  Everything looked fine.   But he said that he'd prescribe her an antibiotic since she's licking her private regularly.  He sent me home with Clavamox Drops 62.5mg/ml-15ml.  I give her 0.9cc twice per day.  So her first dose was the evening of 6-12-09.

5.  Even with all the water she has been drinking, I've noticed that her nose is totally dry.  No moisture at all.  I pinch the skin on the back of her neck and it sticks together.  So does all this mean she's dehydrated?  The surgeon said that they give fluids during surgery so I wouldn't expect her to be so ravenous about water.   

At first she charged her food bowl and gobbled it so fast that it would get stuck in her throat.  No chewing, just ate like she had to fight for her food in her previous home.  That has eased up and I've made sure to teach her that she can't eat until I give her permission.  She has to sit, get in her calm submissive state & then she can "go". 

I make sure that we walk out the door and in the door before her.  She can't pull us around on the leash.  We watch the Dog Whisperer all the time and because she was the oldest pup in her pack, she exhibited some dominant tendancies so we are making sure to try not to allow that.  The first sign was when our baby granddaughter came over and Bella stood on her back. 

I noticed that when she needs to poop, it's almost like she doesn't understand what the feeling is.  She'll jump around and smell her back side & then abruptly sit down so it doesn't "happen" or something.  We make sure to walk her in the AM & the PM.  Since surgery we have tried to limit the extent that she moves around etc.  

I'm just very concerned FOR her.  I am concerned that she's being set up for failure in her taxi training because she doesn't seem to have any control over her urination.

I want to know if there are possibly side effects to anesthesia?  Or possibly being catheterized during surgery? 

Any ideas?