Do any of you have a stage of hyper-awareness in the middle of a WILD attempt?

A little bit about how I'm lucid dreaming. I use WBTB early in the morning (after about 6 or 7 hours of sleep) and return to bed after about 3-5 minutes. I can WILD pretty easily (I've had about 10 in the last few weeks) but I've been noticing that all my successes come after what I used to think was a sign of failure.

When I lie in bed I relax, let my mind drift, and slip in and out of consciousness, which is what I want. I know I shouldn't be too aware of my surroundings and that the goal is to eventually fall asleep while still maintaining a sense of awareness. However, in the middle of relaxation I almost always become hyper-aware at one point. I can feel my mind humming, I can hear what is going on around me (like birds chirping outside), I'm thinking in rapid bursts, my breathing quickens (usually I take a large intake of breath at the beginning of this hyper-awareness state by reflex), and my pulse quickens.

When I first began lucid dreaming I would force myself to wake up, thinking I had failed at WILD and had start all over again. Now, I just lie still and let my mind go back to drifting. After a few minutes (I think it's a few minutes anyhow) I slip directly into a lucid dream.

Does anyone else have this sort of thing happen to them when they WILD? Better yet, does anyone have a physical explanation as to why this is happening or what physiologically is happening to the body to cause this.

At this point it's sheer curiosity since I usually don't have a problem lucid dreaming via WILD. I just wonder if I am alone in this experience.