How do I write and read, being less analytical about the literary use?

I used to write brilliantly before, imaginatively and creatively, but now it's gone to my head that if I stop reading books and preoccupying myself in story, poem-writing, english-kind of activities my writing will falter. Now whenever I write, I analyse everything I think of. Each word seems alien, as if I'm only using phrases I know to make up what I write. I keep analysing my sentence structure, and hope I'm not using too many connectives because there's always that thing at the back of my head-that I wouldn't get such good grades if I didn't work so hard to get them. I believe that I really don't have much talent. I am 12, I know this sounds like a bit of a useless thing to think of at 12. :) Too many connectives indicates lack of knowledge in actual ways to vary sentences, and I feel like I'm only getting away with descriptive language. Can you give me a bit of a lecture to get my imagination back into gear and get me reading and writing with the flow again. Even when I read I feel like I don't have the actual ability, like I'm analysing everything as I do in Language lessons. Adjectives, amount of adjectives, originality. What really bugs me now as well, is that I don't read for pleasure, only to "get back" my skill. Can you help me to get back to my original state?