WBTB issues

[meistersomnius]

So, I recently had an LD through the WBTB technique. The next day I wanted to do the same, woke up after around 4.5 hours, but I dind't have a LD. I also don't remember being that tired in my PSAT (post sleep awake time) after having done this the first time. Is it because I didn't get enough sleep the other night? Because I also don't remember any dreams I had. I think I didn't get enough rest to have good REM phases. What do you think? Edit: This night (the third night in row, that I'm trying this) was terrible. I woke up at like 3am, and was awake for about 45 minutes. Then I went to bed. I couldn't sleep. I started turning and trying to get into a STS. Nothing worked. I wasn't tired anymore. It felt like I was awake until 9am, when I stood up.