What Camera do I get?

I'm a fifteen year old girl and I'm interested in photography and looking to do it as an A level next year, as well as this i'll be doing the standard things including holiday shots/photos with friends/prom pictures etc. My budget is about £400 pounds and i'm after a portable interchanging lens camera with the following qualities:
-optival veiwfinder
-flipout screen
-relatively small
-HD filming
-quick shutter speed
-a number of shooting modes (including panorama)
-good low light shots

The nikon 5100 looks almost perfect but is too expensive
the nikon 3100 is less expensive however doesn't have a flip out screen
the sony nex 5n looks great as its small but i don't know whether the size impacts image quality and it doesn't have an optical veiwfinder. It is also slightly over budget
the lumix g3 is perfect in size/looks but it doesn't have panorama
and the sony a37 doesn't have a flip out screen and reviews i have read have been mixed!

Help, is there a camera out there that does everything i want for under £400?

Get the Nikon D3200.It's the best camera for the money and it's right in your price range.

Yes - the Nikon D5100.
Current price £405 at Amazon: http://www.amazon.co.uk/.../letscook/
Then get £55 cashback from Nikon: http://www.nikon.webfulfilment.com/cashback/christmas2012.asp
Final price = £350

Cashback will be a pre-paid Visa credit card.

EDIT - Don't forget you will need to get a class 10 SDHC card as well.
This one is top quality: http://www.amazon.co.uk/...0037FLUYU/

Also, if your PC does not already have an SDHC card reader, this one is pretty good and cheap:
http://www.amazon.co.uk/...000VY80AM/

You will probably need a case but you can always put that on your Christmas list!
My wife uses a Lowepro Nova 160 AW case with her D5100.It's about £30 at Amazon, but has enough room for a second lens and comes with a water-resistant hood.

For software you can always start with The Gimp, which is free, but you will probably soon want to upgrade to Paint Shop Pro or Photoshop Elements as the Gimp is not the most user-friendly piece of software.