Actually, I seem to experience Deja Vu in much the same way you described. I just feel like whatever small event just happened is familiar, then the next series of events feels the exact same way. I never really thought much of it, but when it does happen I've taken to trying to guess what happens next. I'm never able to actually guess what happens next, but when it happens I feel like I should have known that was going to happen, because it also feels familiar.

I don't think I've had the experience stretch out to last a week though. Just the "I know this" and being confused at whether I know what this is or not.