Dropping out in freshers week?

If I drop out in the middle of freshers week (I chose the wrong course and the university didn't offer the one I wanted), do I have to mention that I went to the university at all on UCAS when reapplying, or will the universities I've applied to know that I've dropped out?

You should mention it in the education section

Really? I called UCAS and they said you wouldn't have to mention it if you dropped out in the first couple weeks. How would the other universities find out if I didn't?

I think they can find a record of it as you ll still have had finance in that time. Why don't you want to mention it?

No; I don't lose any finance! And because I'm hoping to apply for medicine, they want commitment!