Yeah you're right about the RCs. It is helpful that when doing them, pretend like you are in a dream. Lets say you trying to do the finger through palm RC, pretend like you are in a dream and think that your finger will actually go through your hand.
And about your questions. I don't think you did anything wrong actually. What I would do differently though is to wake up after about 4.5 hours (3 hours is a little early) and stay up longer, such as 30-60 minutes (but it's alright if you can't do that since you said you have a slight case of insomnia). When going back to sleep though, I would be relaxed and vizualize a lucid dream I want to have and set an intention that I will have it. After that, I wouldn't think too hard about it, because it's harder to fall asleep for me that way. So I just go to sleep normally after thinking about lucid dreaming. To find the best time for REM for you, you would have to test yourself by waking up at different time each day, and you'll find what time works best for you.