[AyumiFanGuy]

Masa-san,

Here's what I think:

"You see? I on the day
You see? Is nodding behind me"

I think that, contextually, the meaning of this (excluding "you see?") paired with the verse prior to it is that her self in the past is agreeing with her present self. If that's correct, then it would almost be better to word it like so:

"You see? I on that day
You see? Am nodding nodding behind me" (or "Am nodding toward/at me", but that's probably not the meaning of the Japanese word...)

Grammatically, in English you would't say "I, on that day, is nodding behind me" because it's incorrect English. The proper phrasing of that sentence would be "I, on that day, am nodding behind me." Hope that helps. It is grammatically incorrect to say "I is" - "I am" is the correct way to say it. ^_^