I'm not super familiar with English/KCL entry requirements but really don't know what you are worrying/complaining about. as far as I can tell their requirements for English are AAA in A level subjects. Given your GSCEs, if you keep working hard and enjoy the subjects you take, you will get those entry requirements.
You have done very well in English which is a good indication you will manage just fine studying it for A-level, you have also done fantastically in other essay based subjects so I wouldn't be worried about your A-level performance. You passed all your GCSEs so I don't see what is so "awful" about them, although perhaps your expectations for yourself were higher. Unlike what teachers say, GCSEs aren't the be all and end all, welcome to the real world now. (Employers don't give a toss what grades you got and neither do unis)