Please Help Me! Which Sixth Form College Should I Go To?

I'm so stuck! Any advice would be very appreciated!

So right now I'm at a very big 2000 people sixth form college which I hate, I've been there for a year now, and it hasn't got any better, I didn't know anyone when I arrived and was too shy to infiltrate anyone's friendship groups (most people came with their friends). Because of this and some other reasons i'm really not happy where I am so I am definitely moving colleges next year but I have two options and I have no idea what to do

The first choice is my old school, it's much smaller than where i am now, i think the sixth form has about 30 people in, and I know a good lot of the people there, the problem is I think the dynamics may have changed a lot since I left, people are different, and new people have come and new friendships made, I just feel like I won't really fit in there, I've kept in contact with a few people, and I was quite well liked when I was there, I just don't know if now it would be too weird and different for me to go back there.

The second choice is a different sixth form college, it's also smaller and I don't know too much about it, it seems nice enough, and also my best friend from my old school who also moved to a college may be going there, but it's also expensive (yes its a private college, so is my old school, please don't judge me) whereas my old school is less expensive, and i'm not sure whether it's a little too prestigious, they'll probably care about my grades (which aren't great), where as my old school will likely take me back Straight away, I just don't know what to do, any advice would be completely appreciated