Don't know what to do about uni anymore.

Hey so basically I'm in a bit of a pickle For the last few months I decided I was going to pursue a physics degree and I've based all my extracurricular activities and experience for my personal statement. I've just went along with this in my mind and now its hit me how I really don't want to study this and now I'm just panicking. Now it's a long story but I can't take a gap year and I'm really panicking as to apply for another course I have nothing to talk about on my personal statement for another course and I just really need to calm down. Is it possible to get on a degree course at a top uni without relevant experience or is it essentially crucial. Agh it is such a mess I just wish I had more time :/.