Lately, when I've tried to meditate, I find myself slipping into sleep paralysis after fifteen minutes or so. First, my hands will start to go numb, then the mattress will start to feel odd, almost like it's gone from being soft and cushy to being more like clay or putty. Before long, I'm starting to feel like I'm sliding or rotating slowly, and I'll get a feeling like I'm very close to slipping into a lucid dream, like I could sink through the bed and find myself dreaming.

The problem is that, when I reach "the edge," I keep getting pushed back somehow. I'll move my hand a bit, or I'll get excited and my heart will start beating quickly, and I'll have to relax for a few minutes to get back to where I was. Does anybody have any advice for how to get over this hump?