If you had been able to kill most of the wasps without killing any bees, the queen bee would have taught you a level of a spell (Elemental Strike or Elemental Hail, IIRC), but there is no great need to reload.
To successfully complete that quest you pretty much need to avoid area effect spells and use the control key to target the nearest enemy to your cursor. The first time through as a warrior I also killed a few bees with the swirl attack, but I reloaded anyway to take better advantage of the level-up jug. I left the imp council quest till last and waited until I was just about to go up a level to get a larger experience bonus from the jug (ie level up killing wasps, then get another full level from the jug).
