I'm going to give you some serious critique here so please try your best not to be offended. I took the 10
minutes to write this because I want to help you make this better not because I have nothing better to do.
There is way too much exposition about her friends and teachers etc. It's boring and sarcasm isn't funny.
Remember: show, don't tell. Rather than telling us that this person is this way or that way, have the two
have a conversation where (e.g.) Brenda shows that she likes her style and doesn't care what anyone else thinks.
Also, far far less about Kevin please. There's no need to go on and on about an utterly one-dimensional
stereotype character. "He's a window licking loner bully" would suffice.
I like the basic idea of a lonely tough girl who gives into her libido (as opposed to being blackmailed or some shit)
but you're trying to jam the whole setting into one incredibly long monologue and 99% of people are going
to give up on it 5 minutes in.
If you're going to stick with the diary thing, maybe her teacher instead of reacting with surprise that Amy was
vulgar in her diary (what was she expecting?) she could offer some insight like: "a diary can't judge you, you're
judging you." or "maybe if you were kinder to your friend you could learn to be kinder to yourself too"
Minor point: I took the "lets spice things up" choice to be about whether I wanted BDSM scenes or not, but
it seems that it goes around hiding all kinds of sexy pics later on. I realize you're writing this in the voice
of a teenage girl but be clearer anyway.
Copyedit: "emphasis on the somewhat" in a dialog that doesn't have the word somewhat.