First, go to the vet. Loki has nighttime incontinence. At first we also weren't sure if he was peeing in his crate or what, but we also watched him sleep for an hour and he woke up wet, so we KNEW it was unintentional. The vet put him on a drug called PPA, Phenopropanoalamine (I think that's spelled right.) As long as I give him his medicine we have NO problems. Plus, the medicine tastes like meat so I don't even have to coax him to eat it. I keep it in the bathroom with my meds and I wash his face, brush his teeth and feed him his pill. So, it's really NOT the end of the world if that's what the vet says. In his case, a muscle holding the bladder shut just doesn't close tight enough and when he's sound asleep it relaxes. He doesn't leak during the day, and even at night it was never a leak but every 3-4 weeks or so he'd basically wet the bed. Even limited water before bed didn't help. We also would set an alarm for 2am. Finally, once we got the medicine, he slept through the night and has ever since.
Loki also drinks too much, which just compounded the problem before we knew what it was. He probably drinks 4-5 times as much as he should, but I've had him tested for stuff and our vet is aware of the problem and he just apparently loves water. I do limit the water because he is obviously getting enough to drink when he goes outside every 45 mins and pees a river. We also started with a water bottle when he was a baby and he would drink the whole bottle every time we filled it. He stopped getting water in his crate because he wouldn't save it - he would just drink it all right away. I just make sure he gets enough throughout the day and he's fine if he needs to be in his crate for a couple hours.
(I guess my point is... don't wait months to go to the vet like we did... because if it's something medicine you can get started right away!)