If you purposely have a false awakening, you will probably have a false awakening.
If you try to wake yourself up, you will probably wake up in real life (or have a false awakening if it doesn't work). I do this by closing my eyes and concentrating on my real body.

If you find yourself going to the bathroom a lot that means you have to go in real life. In normal dreams nothing happens but I wouldn't try to pee in a lucid because I think it may be possible that when you're close to waking up you do it with your real body instead of your dream body.