Crush, I'm not saying you did anything wrong here, but if a plant takes 10 or 20 day longer than usual to finish and the high is couchy then perhaps it was harvested a little later than ideal.
Plants will take longer to finish if they do not receive ideal conditions.....a 60 day flowerer can take 80 days if things are not right....this might be due to several compounding reasons eg a slightly higher than ideal pH level, slightly wetter soil than ideal, too much ferts, insufficient vegging time for seedlings etc etc