Too much awareness?

I seem to be in a bit of a predicament. Pretty much all the lucid dreams I've managed to get after engaging myself with this (and they'r not a great many) have been attained via reality checks, usually due to an odd occurence.

I've been attempting to perform a MILD several times, though I've found that mantra-type repetitions of sentences like "I know I'm dreaming" cause me to become too wary, so to speak, so whenever I catch myself drowsing off my body jolts me awake. It almost feels like an electric surge.

Any ideas on what could help improve this technique?

Actually, MILD doesn't require you repeating a mantra as you fall asleep, that got thrown in somewhere along the line. Just keep your intention in your mind, you can do this without actively repeating any command. It's a balance between focusing your intent and being able to fall asleep normally. You want to be as focused as possible without disrupting your ability to fall asleep. I reccomend you read the MILD section in EWOLD.