Held Ball at the end of the 30 sec shot clock

[rbruno]

Just happened tonight and I feel we messed it up. NHSF rules in Massachusetts.
White is shooting and the 30 sec shot clock is winding down. The ball never hits the rim and we have a held ball just BEFORE the horn sounds the violation.
The arrow is in whites direction. My partner and I confer and agree that the whistle for the held ball just preceeded the horn but with less than a second left. We can't reset the 30 sec clock to less than a second. My partner thinks we have to reset to 30 sec and give the ball to white as it is their arrow.
What should we have done here????