Did she definitely misgender you? I get pissy sometimes when someone calls me 'love', or similar, because I take it as a feminine term, but then sometimes I hear them say it to a tattooed hairy thirty year old guy behind me, so who knows. I really can't see it, bro. The way you carry yourself maybe? Your voice?
As for the cutting, find someone to promise that you won't do it, and who can tell if you do. That's how I managed to stop. I substituted it with burning and punching myself (sounds stupid) for a while, but eventually the need to went away. It definitely helped knowing I'd be letting someone else down by doing it again. So... promise us!