Hi
Please don't talk anymore about age as it is making me depressed!!!!!! I am much older than you so you've got nothing to worry about.
You will get funding for the length of your course plus 1 year. So if you drop out now, you will still get funding for the length of your new course. If you need to repeat any further years, you would still get the loan, but no grants or fee loan.
How your money is affected depends on how you were assessed. If you were entitled to any grants, chances are you will have to pay some of it back. Your loans and grants are calculated from the date of withdrawal, so once withdrawn, you will get new notifications showing your entitlement for the period attended. It is unlikely that you would be asked to pay any of the loan back even if you are overpaid. (unless you get a job and after April you are earning more than £15k).
You could stick it out for the year, and still transfer or reapply for next year (obviously if you are going to reapply you need to do so before 15th January). Another uni may even accept you into the 2nd year if you successfully complete year 1 of your current course.
I'm sure your parents will understand if you explain to them how unhappy you are. And to be honest, one more year will fly by (they get quicker as you get older!)
If you do decide to leave you must inform your LEA straight away in writing (or CO1 form), as it is a condition of your loan that you inform them of any changes straight away. Still receiving the money if you are no longer entitled to it could be seen as trying to defraud the system, and you don't want that!
Whatever you decide to do, good luck with it. But it is better to withdraw now than continue with a degree that you may not pass because you don't like a large element of it. At least if you withdraw this year you will still get funding for a new course.