Can you tell me what grammar/punctuation mistakes I have made in what I have written of my essay so far?r?

Have you ever closed your eyes and stopped to enjoy the feel of the cool breeze on your face, the soothing smell of grass and the sound of the birds chirping in masses? Then in what you couldn't imagine a more peaceful moment ,BOOM, you find yourself slammed down to the ground by the impact of a fist. Well, this very thing happened to me. As pain shot from one place to another, I didn't have time to think, at least not for a few seconds which was long enough for them to take another shot. As I began to realize what had happened I found myself with a mix of rage, fear and confusion. A quick dose of adrenaline pumped through my veins. I couldn't run, my only choice was to take the blows to my thin,boney body or fight back. Me, being the school nerd who looked the part too was no match for the three ninth graders charging quickly
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