I've been trying to WILD for about a month now, since when I was trying different techniques earlier I entered SP while WILDing but unfortunately I didn't know that I was in SP and so I blew it.

Anyway, now when I try again after a WBTB I always reach to the point where I begin to enter SP and my legs start to feel numb and heavy, but ALWAYS after that I drift to sleep. I tried to concentrate harder not to fall to sleep again but I always fail. What's going wrong?