I can identify with the poor guy. I have a scheduled appointment next month with the doc (not the same one) and I have a hunch I'll be getting the ole digit treatment. When I have to go there best be a bathroom close by, or I'm in trouble. I don't know if dogs have prostates, but he's a male, so I suppose it's possible.
The vet's office want's a urine sample (Benny's). I had to ask how to get it since I don't remember ever bringing that kind of sample to an appointment. She said that some people use a ladle, which I think might be too small considering my lack of experience so I camp up with a crisper drawer from a junk refrigerator that resides in the basement. Cleaned it up good with a bit of bleach. It has to be clean, but not necessarily sterile. I think they'll be testing for diabetes (hopefully among other things) since she mentioned not to use a jelly jar or something like that which might have residual material to screw up the sugar count.
Anyway, all I can do for now is send him out often and change the cover of the bed when necessary. I have the ceder part covered with plastic so it's only the cover that will get soiled. He stands at the top of the steps and looks at me like, "what, again"? But I tell him to go wiz and he does.
The pictures below are from yesterday's balloon jump from 23 miles up. Mick did a good blog with details about it "Jumping from the Stratosphere". The blog is about 8 posts below this one.

Ready....... Set......

I took this screenshot a second too soon, but you get the idea. The curve of the horizon is exaggerated due to the wide-angle lens, but they say you can actually see the curve from that altitude. Never catch my sorry old ass up there. Skydiving was something I had wanted to do, but now I figure, I lived to get old, why risk it.
Positive vibes for Benny.... Hopefully I'll have something positive to say on Thursday...