I've had these thoughts before. I'm a crammer, i don't really listen in lesson, i wait until deadlines are just around the corner before starting coursework etc. etc. but i know that i'm going to have to change this for uni, i know you can't get away with that at vet school. Like someone said, if you really do enjoy what you're learning about and love the course, you'll put the effort in.
And one of my worries is the opposite to yours, i absolutely love clubbing, being out, being with other people, i'm never in, i'm just hoping i learn to say no tonights out at uni so it doesn't get in the way of my work!
If you want it enough, you'll make it work! x