I tried WBTB'ing for over a week, really decided to have lucid dreams. But had 0. And waking up at 4:00 am was simply too much effort for so little reward.
That mindset gets you nowhere. Just saying. You are what you think, and you are what you repeatedly do (Aristotle). Try being confident.

To be honest, school is probably the big factor here. I usually never have lucids on school nights, since I wake up at 6:40. What I have noticed is that every LD i've had has been around sometime I can think and function properly. Not 4AM, but 8/9 AM to 10/11 PM.
Anyway, just be confident that you can do it and you will. Trust me, I've tried.

EDIT: just saw your P.S.
MAybe use that as an RC? Are you nervous in your dreams, or do you feel calm and relaxed? My guess is the latter.