I think you have two threads going here --
I know you're new -- and welcome! I think you'll find there are a lot of helpful folks here -- most of us pretty dog saavy. But do yourself a favor? Most folks are pretty bomb-proof - use the real words? #1 and #2 only have meaning to certain folks. That was never used in my home -- I had to read all the threads to try and figure out what the heck you were saying? urine or ***? pee or poop? No one is going to get offended and it might get you answers quicker, truly! *grin*
There are several tests the vet can (and should) do.
in house (right at the vet clinic) the vet can take a sample of caught urine and dip a strip in it and by the color it turns typically they will try to determine if there is infection or not. They're not infallible, and particularly for something that may have gone on a while you want a better test than that.
Also -- they can simply take a caught sample (you can get urine from a dog either by "catching" it in a sterile cup or pan OR there are two ways of getting a "sterile" sample -- meaning the dogs skin can have bacteria on it that can skew the test -- so a 'caught' sample isn't the most reliable in any event) -- but they can just take that caught sample and send it out to a lab. Typically that takes overnight -- but you'll also find out if there are casts or crystals in it that can be causing pain and problems, as well as finding out if there is infection present (infection that might not show up on a test strip).
However -- I'm going to suggest you go for a better test than that even -- a 'sterile' sample is either taken by cathether (a plastic tube they insert up the urethra past the urinary tract into the bladder -- so it can tell the difference between a simple UTI and a kidney infection for example) OR an aspirate (they take a long needle and a syringe and simply suck urine straight out of the bladder).
But with a sterile sample they can do a test called a 'culture and sensitivity'. The regular lab work will tell if there are casts, crystals, rods, etc. -- BUT if they find bacteria they simply culture that bactera into several petri dishes and literally 'grow' whatever will grow from that bacteria sample. Then they use several different antibiotics to *kill* that bacteria. This way not only can they fully identify any bacteria present, but they also know exactly what drug to use to kill it the best way possible.
Some vets will simply do the cheapest test they can ... the strip test. But it's not conclusive and since you're having an ongoing problem that might be physical and might be behavioral ... you really need to *know* for sure what's going on.
THEN -- you can re-train Amber.
But the vet saying she should be able to hold it 5 hours? That's not helpful. A pup of a certain age MAY be able to hold it a certain number of hours based on their age. But that's with **training**
And for some reason this dog isn't getting it.
But honestly -- you can *not* assume that any dog is completely aware of the goal of not going in the house. Most dogs simply do whatever works **at this moment**. And if they have successfully been "hiding" for months? That's what they will do.
Can I ask? How old was this dog when you got it? It doesn't take long for a dog to learn very bad habits -- habits that it just can't figure out how to break.
MANY dogs simply learn fast that you don't "go" in front of a human. Because that human may holler at them, hit them (not you -- but perhaps a former owner? even as a baby puppy?) or in some respect have a hissy fit. So they do whatever they gotta to in order to NOT go in front of *You*. If you are outside *with* them then they may think they ***gotta*** wait til they go inside To go. And they just think all this yelling and bad grace the humans show is just ... well, the humans don't like me!!
Have you tried leashing the dog TO you. Every single second while you are home? And you **watch** the dog for signals -- like sniffing or circling ... to show you that they have to go? then you go out with them the instant they indicate they've got going on their minds.
But when they screw up -- go put them out of sight (don't let them see you handle their waste -- it is somehow reinforcing to them) -- but pick up that waste (either kind) and go put it outside WHERE you want them to go. then, go get the dog **on leash** and go show them you **MOVED** their waste. Yep -- you want it **there!!**
Next time you think the dog might have to go you leash them and take them straight back out to that paper with the waste on it -- yep -- I want you to go ***HERE***.
There are many ways to do this -- but honestly, I tend to do it this way rather than just scheduling. And Amanda's bell on the door? IT WORKS!!