Im at HTX Slotshaven EUC in holbæk :)Hey Levis. Im a dane too, and i am currently on my first year of a bachelors degree in physics. I just took my exam in Linear Algebra today (i noticed your remark on how simple vector operations are :) ) and i feel that i can safely tell you, that if you are already this proficient with mathematics (just the fact that you know enough calculus to be constructing differential equations) and if you continue to challenge yourself like this until you reach your first year of university, you are going to have a pretty easy time here.
by the way, im studying at KU. What gymnasium are you at?
Just to give you guys an update; I contacted my teacher, and he was feeling the same way you guys were. He has asked the advisors at the university of Copenhagen, whether i would be able to start even though i haven't got a high school exam. Usually you can, if you can show the same qualifications as one with a high school exam - this is not a problem in math, but i'm not that good in danish class... So i can't be admitted this way. The advisors are currently working on getting me admitted through somekind of loop hole in the university regulations. If that's not possible they will attempt to get me a dispensation.
If all this works out - and i'm afraid it's not possible though - i will most likely be able to start university after the summer break :) If so, i will by then have read all the mathematics for high school, so i'm able to follow and complete any kind of admission tests, they might give me :)