it's very possible that once you've arrived here, sussex lets you switch to a media/english degree, even if you don't have the grades.
and regarding media studies, unfortunately it does have a reputation as being a subject taken by those who were not academic enough to take further maths and chemistry, or who struggle with english, politics and history. the fact that there are lots and lots of media students means that just doing a media degree will not at all render you likely to get a job in the media- there just aren't enough jobs for it (and the bbc would probably prefer an english student who had worked on the student paper and radio station).