Quick Sodium Question

SunKissed1989

So, this week I have been watching my sodium levels as I think I've been retaining water meaning my weight has stayed the same for about a month now.
I was just wondering, when it comes to sodium, as with calories, if I'm under by say 200mg one day but over another day by 200mg in the same week does this 'even the score' as it were or does the fact that I'm over by 200mg mean that I could still be retaining water weight for the week?

Any info about sodium, water weight and the likes will be greatly appreciated.

Thanks