Is this the effect of lucid meditation?

[SpecterSlash]

I read somewhere about how to meditate on lucid dreaming. The instructions were to breathe in and out and think that the air is visible. The other instructions were to focus on the back of your head but the main thing was to focus on either of those things. It say that I mustn't lose focus at all. I practiced it for 3 nights and on the 4th night, something weird happened. I don't know if this is what you're supposed to feel when you meditate. I'll try to explain it as detailed as possible. My eyes are closed but I'm wide awake. I could feel that my sight gets blacker, when you close your eyes its black but mine became way blacker and I could see little white waves moving around. I know I am still wide awake and in full control, I'm pretty sure it wasn't a dream. I could barely feel any other sense other than the cold air and i kept feeling my heart beating. This is where it got scary, the only thing I could feel was my heart beating, It got faster and faster. You ever tried focusing so much but the saliva in your mouth keeps building up and you have to swallow? I opened my eyes but I am still 100% sure that I wasn't dreaming yet. I was still wide awake, I noticed I was extremely sweaty even though it was cold in my room. It was a scary/exciting experience but im not sure if this was part of the meditation.

[SpecterSlash]

bump anyone help?