I don't know if this will help anyone at all, but I thought I read that one of the LD techniques requires you to wake from a REM stage.

This is very awkward, but may tell you if you were just in REM !

As not to put it in my own words and make it sound even worse than it already does, I'll just quote the website. (the highlight of what I'm trying to get across is bolded and underlined)

REM sleep (Dream Sleep) – At about 70 to 90 minutes into your sleep cycle, you enter REM sleep. You usually have three to five REM episodes per night. This stage is associated with processing emotions, retaining memories and relieving stress. Breathing is rapid, irregular and shallow, the heart rate increases, blood pressure rises, males may have penile erections, and females may have clitoral enlargement
The link to the website is as follows: http://helpguide.org/life/sleeping.htm

So if you wake up like this, now you know why

Hope this helps someone