1 - At this point in my progress, at about 20-25 minutes into a session I will get involuntary shivers starting at the neck and running down into my legs. This will happen repeatedly maybe 5-10 times in quick succession. Then maybe 5 minutes later I will get another series of them, and so on. They are sort of pleasurable but not mind-blowing. I also seem to be able to initiate one weak pulse at will (which doesn't repeat), and I can even do this when not meditating. What does this signify? What stage am I in? Are these the "vibrations" everyone talks about?
Maybe 1st nana, maybe 2nd nana, maybe 3rd nana, probably 4th nana, maybe 5th etc...
More info needed.
2 - When I get to #1, I try to shift my attention to the shivering and note it, but the vibrations in it are really too fast to note. Any ideas here?
Note "vibrations", maybe note also the tone of vibrations, pleasant, unplEasant, neutral. Eg. Vibrations-pleasant, vibrations neutral.
3 - Sometimes I'm not sure what to call a sensation, and by the time I figure something out it has long passed. Or I am afraid I am calling two slightly different things by the same name. Any advice?
Howabout noting it as "sensation" or "confusion" or "vibrations" or "pleasant" or "unpleasant" etc?
4 - When is the right time to stop doing the noting and just pay attention?
Usually in high equanimity. But it will feel quite natural and possible to do so. All phenomena will be easily seen to arise and pass without the need to note it all.
5 - I don't detect any vibrations in my breathing no matter how hard I concentrate. I seem to be altering the breath pattern by focusing on it. Like it comes in huh-huh-huh in half second intervals. Is this vibration?
Why are you looking for vibrations? If you are "looking for" something note the mind state of "looking for". Stop worrying about what is vibration and what is not vibration and just note what you observe and what is occurring right in the very moment. It's not looking for it's looking AT!
6 - Sometimes my body will jerk or my ear will twitch. What up with that?
A body jerk, an ear twitch. Note it and move on. It's not important. The process of insight will undo a lot of physical knots. Let them untie themselves.
7- Sometimes I will find that I have something like falling asleep and jerking awake, but it's different than that. What's that?
Falling asleep and jerking awake + speculation/proliferation/wishful thinking/scripting? More info needed to speculate and proliferate further. What happens right before such jerks and right after such jerks, phenomenologically speaking?
8- I seem to have a very mild throbbing headache in my forehead since I have started. Ideas?
Mild throbbing headache? Again, the process of insight unravels a lot of stuff. Let it happen and note it when it does.
9 - When breathing, how should you note the breath. I notice it continually so do I say "in-in-in-in" really fast? Do I say starting or ending or stopped or something else during part of it?
You could note "breathing in", "breathing out" maybe, or just "breath", or "touch of breath" or "in" and "out". You don't have to note continuously like that if it feels odd. It doesn't matter what you note as long as you
notice the breath. One "in" and one "out" was enough for me. In the spaces in between noting, the mind was aware of the breath still. Noting just keeps you on track and aware of what is noticed. If you are noting so fast that all you are aware of is the noting, then you may not be noticing what you were noting originally. Noticing is more important. Use the noting technique to be able to do this and stay on track. It doesn't have to be very fast. That is one way to do it. Here are two techniques i used:
http://thehamiltonproject.blogspot.com/2011/01/yogi-toolbox-fast-noting.html
http://thehamiltonproject.blogspot.com/2011/02/yogi-toolbox-detailed-noting.html
10 - I will often get random odd thoughts pop into my head. Also I seem to often get mental images of different odd faces and creatures of some sort popping in. They are detailed and are always something I've never seen before. any thoguhts?
Note the thoughts as "thoughts" or as "planning", or "worrying" or "speculating" or "wandering" etc. Note the images as "images" or "seeing" or whatever you feel comfortable using as a term to objectify. By getting sucked into the scenario or theme of the thoughts and images the mind may begin to proliferate of of them. This is called
papanca. Note the hell out of it.
My 2 cents.
:-)