@sky-chic No worries! And again, I cannot stress enough that you have to have fun and not focus too much on mistakes. You just have to acknowledge them and move on.
The very first thing I wrote was a hugeeee learning curve for me, as it was basically a giant experiment! I had a blast at the time, and even though people pointed out I was mucking up a lot (trust me, it was quite interesting - I still have all my old stories on one of the computers and will go through them on occasion for nostalgia's sake) I just had a blast doing it!
For what you seem to be going for, and probably because I'm re-reading it, might I suggest giving "The Hero and the Crown" by Robin McKinley a read? It may help give you some ideas, and I know she uses an interesting voice throughout it/really plays with how she arranges her words in sentences to manipulate how it "reads". I know the worst part of editing for me is how much word swapping I have to do in different sentences.
Like what you've already been doing, reading a lot really, really helps. The more I've read, the better I've been able to spot my own mistakes. But I know how elusive it can get! Plus, when you've just written a draft, it takes time to be able to get enough distance to "read" it without correcting unwittingly in your mind as you do.
Ohh! Science! =D I like the sciences, but my math skills dragged down the possibility of going terribly far in them, haha. I've always been an english nerd, though I've never taken it farther after school. Thought about it, but so much of it is focused toward Literature, and I'm a big lover of genre novels. Go figure!