How easy is it to transfer University? When can you do it?

Hello.

I love my course, and I got into my top uni. However, I really don't want to be here, I'm beginning to feel depressed.

I have people to live with next year, but I'd much rather live at home. I don't want to sign a house contract with them because I feel as though it will tie me down to staying at this uni for another year.

The courses at this uni and my local uni are almost identical. I feel as though if I want to transfer, I have to make my mind up now (as 1st year doesn't count at either university).

I am also worried that this feeling will go, and I will have transferred from my top uni choice, and therefore will have wasted this opportunity.

Also I didn't get the grades to get into either University, but they let me in here anyway, will this stop me from being able to transfer?