Are you relaxed while you're doing this? If you have an active mind you aren't going to go anywhere, since your body knows that your mind is still awake. The whole point is to trick your body into entering a dream state while your mind is secretly awake, but to do that you have to stay still, relax and don't think too hard. You should try to notice the HI but don't concentrate too much on them. Also, are you attempting this after 4-6 hours of sleep or at the start of your sleep? It really helps to wake up during your REM period. It's normal to feel the paralysis early on; I feel it after about 10 minutes of staying still. I hope this helps!