Is this SP?

I've been attempting to WILD for a few weeks and can consistently enter a state of what I would best describe as semi-paralysis. I have the feeling that if I really wanted to move I could but there is a soft barrier between myself and mobility. I also lose the ability to pinpoint my limbs spatially, almost like I'm non-corporeal (which I'm not, I know where they are. I just can't feel them). I've never entered WILD from this state and I was wondering if that's because its not SP or I'm not doing something cognitively that spurs the transition.

This is basically just, going numb after laying still for awhile. This is not sleep paralysis. When you enter sleep paralysis consciously, such as during a WILD, you really can't miss it or mistake it for anything else. For most people SP involves loud, sometimes violent rushing sounds or throbbing sensations in the ears and intense vibrations throughout the body. If you aren't entering SP this is most likely because you are too alert/awake. WILDs are extremely difficult because to be successful at them the mind needs to be awake enough to remain conscious through the transition, yet not too awake as to keep you from progressing into SP. It's an extremely narrow range of consciousness, and a lot of it probably has to do with luck and more so, timing.

Thanks! Does this "numbness" usually precede SP or does it mean that I have overshot my window and need to reset and try again?

It's before SP. When attempting a WILD from a normal waking state (not like a WBTB or something where I would be more inclined to be tired and get to sleep/SP quicker) I usually get the full numbness within 10 min. For me, SP may not come on for a good 45 min. It's different for everyone though and depends on how much sleep you've gotten.