Let's say I arrive outside my friend's house. He's expexting me. I need a cigarette, so I smoke one outside. I see my friend in the window. He sees me. I finish smoking and walks up to the front door. My friend opens the door. I say "I just needed a smoke" to explain why I kept him waiting.
It seems natural to me, but I'm uncertain about what "just" means in this scenario?
I don't intend it to mean "only" or "I just so needed a smoke". I can't explain what I intend it to mean, and I'm not sure if any of the definitions I found in the dictionary is the one I'm looking for (it probably is though). So what could it mean? And what would it be taken to mean in my context? Thank you in advance.