Ronin

Fear uncertainty and doubt; If they tell you that it wont be on any records relevant to your further scholarly career, or that they wont even last that long, this means, that they are meaningless, but just made to shock you and your parents.

Take it as it is, a warning without any direct consequences; If you don't break any boarders from now, you wont get into any kind of trouble.

They are probably pushing each other in such an argument and will therefore always come up with the most sever and maximal punishment.
For the next times, stay cool, tell them that it's a joke, that you don't really care if they find that kind of humour indent, because you don't rely on it and that you wont do it again if they or anyone else feels insulted, you know what I mean.

It's a bit over the top to scold you for what you have done, but that depends on the climax of your school and where you life.

Do NOT tell them you where misunderstood, that would mean that you where right to do it and they where wrong.
Fuzzy talk them and have them admit it wasn't such a big deal is all you should go for at best. Don't be a complainer or youll get shoved over the boarder of earth quickly.

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