About your fear. The trick here is to have a non-committal answer ready in your mind in case he asks that question; which he is unlikely to ask anyway.
If he asks, why you are in a cubicle reply in an off hand way either "Don't like troughs" or "I prefer cubicles". If he comes back with why, just repeat the answer "Don't know, just don't like troughs" "Don't know just prefer cubicles". It is not massively interesting to them. Don't elaborate!
As to not peeing in from of them. If he notices and comments like "what happened?" again just say "Don't know, sometimes it doesn't happen". There's a chance he will say " happens to me sometimes".
We make the mistake of thinking our peeing or not peeing is very interesting to others. It isn't. Peeing is off the bottom of the scale of interesting. Its equivalent to not being able to blow your nose; difficult to show much interest in that isn't it?
Hope that helps
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