If you consider dissociation on a spectrum or continuum, then we all can be said to dissociate once in a while. Just like everyone can be considered at least a little bit Borderline if you judge that disorder on a spectrum. The trick is to know when it's disrupting your life, but that's something you can probably figure out for yourself. I mean, if it's causing you distress and hurting your social or professional life then you probably need to confront the problem, but if it's harmless and you zone-out/daydream every now and then you needn't worry simply because you've applied the stigmatic label of 'dissociation' to it.

Of course, it can be helpful to know you're doing it if you're still trying to understand the diagnosis of a Borderline personality disorder.