ah. those things that are prohibited, and you don't do em, BUT there's this one time that you do for a good reason or you just do accidentally (like in your case) and THAT'S WHEN YOU GET CAUGHT/SCOLDED FOR IT. I've had my fair share of those.
last year (in our senior year in highschool) we NEVER do homeworks and assignments at home. only in school, in the morning, on the day of the deadline. and 80% of the people in our class (that was just an estimation, but I'm sure that it's way less in other classes

) just copy someone else's work (I'm part of that 80%

) and we try our best not to get caught. we don't, but our teacher knows that it always happens, she's just so lenient about it since the quizzes and exams still show who really learned and who didn't. we look at homeworks and assignments as just bonus points and practice exercises.
anyways, there was this one evening when we had an assignment in Physics, and since I had this friend/classmate who was online on Y!M decide to help each other out with whatever the other one's having difficulty in the assignment, we had everything done even before my bedtime. the next morning, right when the school bell rang she saw my paper and pointed out something I forgot to show (some solution/equation and shiz) so I asked for hers and copied what I missed (just to save time) and BAM our teacher literally appeared from behind, ninja'ed my ass and there goes the effort.
and that was the ONLY homework/assignment I've EVER DONE AT HOME. never doing that again lmfao.
just sharing.

whoa wall of spam text, I'm sorry lol.