What's wrong with my pup? (Health Q)

[hamster]

A couple of weeks ago, our 6 month old lab started showing signs of a bladder infection. When I took him outside he would pee about 5 times per out, with less and less urine each time, and he'd been licking that area more than normal. Then he wet his bed in his sleep. I took him to the vet and had a urine sample done. While the urine was very diluted (he's been drinking a lot!), there was bacteria and an elevated white blood cell count present. The vet prescribed him 10 days worth of antibiotics, which ran out on Monday evening. Yesterday morning I suspect he went the bed again, although it was a different bed so the fabric doesn't react the same way to water as the other one so I can't be certain. He also started doing the short pee's again.

I've got a morning urine sample to take to the vet today to do another analysis, but something seems off to me. In addition, he's had a couple of hots spots on his back paws, and started to get a third on the front but it seemed to clear up after just one application of hydrocortisone spray. His back feet between the middle toes was also quite red and had some bumps, almost like blisters or cysts. Not large, but noticeable. They seemed to have mostly healed at this point in time. He also seems a little itchy, but then again, dogs are itchy. No changes at all to his personality.

Based on this, my initial Dr. Google diagnosis is some kind of allergy (presumably food) or a yeast infection. We've got him on a high quality, corn/soy/wheat free food, but obviously that doesn't mean it's not possible.

I'll obviously be discussing all of this with my vet, but does anybody have any insight?