Sometimes focus is a good thing - sometimes not such a good thing. It might be that you were focused on one aspect of the task at hand, ignoring all else to deal with this one thing.
Something got in the way of the task - buddy called dive, you ignored it and went back to the task at hand, and I would guess right at that moment you were annoyed that you were interrupted in solving the problem.
Happens to me all the time, not in the water(yet), but elsewhere. I get really focused on one thing and the more difficult the issue is to resolve the more focused I become - to the exclusion of other important things. Has its benefits when trying to solve really difficult problems. Can kill you in the water if you start to focus on the wrong things, particularly if your normal problem solving abilities are impared.
Just a caution that if you are this kind of person, you need to be aware and take steps to override the personality trait whenever you are in the water. My mental trick is to make the task a successful, safe dive - everything else is secondary - getting the great shot, finding a particular critter, navigation, practice, whatever - all come second to the "problem" of surfacing safely. Seems to help me keep myself focused on the really important task anyway - so far.
If you are not normally this way then file it, be aware and move on.