/sneaks in
If it's difficult or not, scary or not, really depends on what you've studied in High School and what you study at Uni. In High School I hated everything except Maths and Physics, which are like 20% of what I studied in three years (in the last year you can choose between Physics, Chemistry, Biology, Geology and some other stuff). Now at University, I'm studying Engineering Physics which is mostly Math and Physics, with a little Chemistry and Programming in-between. I like it much more than High School but it's like 10x harder.
Still I worked almost nothing in High School and finished with an average of 16.something (max is 20), and now at the first year of Uni I have craploads of stuff to do and study, I've done like 10x more work and effort than in three years of High School, and still I'm currently at risk of failing in a couple of subjects in this semester.
Physics...
/sneaks out