My brother stayed on at Sixth Form because he wasn't sure what he wanted to do. Hated it. Sat his AS Levels (failed most of them because he hated it), then left and went to college to do art & design, as he'd decided he wanted to do fashion design. He absolutely loves college and is applying to Uni to do fashion design. The Universities won't take A Levels for the courses he wants - one of his friends decided to do fashion design too but did A Levels so she has to do a Foundation year in it before she can apply for Uni. So no, A Levels aren't always 'better', and there's no point forcing yourself to do something you hate as you probably won't do very well as the motivation isn't there.

As Pegasus said, ask your teacher for advice, but also research Uni courses you fancy and see what requirements they have. They may not care about A Levels.

All the best,

*Willow*