You're not leaving Sunnydale. The correct decision to avoid hurting others with certainty would be to avoid people altogether, but well.. you're not that much of a self-sacrificing paragon. Sunnydale has been your home your entire life- you don't want to leave. But that still leaves you with a number of problems to work out. First of all, the sun is rising soon, and second of all, you need to find a source of animal blood to sustain yourself. Not only that, you need a place to stay, and ideally some kind of long-term goal besides just existing. It feels completely overwhelming, but if you take it one step at a time, maybe you can make it work.
As it turns out, your weakness to sunlight isn't as dire as you'd feared. Your skin starts smoking upon direct contact with sunlight, but you aren't immediately incinerated. The skin covered by clothing is unaffected, and shade from the trees also protects you. Still, your outfit is distinctly warm weather gear, so you can't really leave the graveyard yet. You spend the day in the crypt alone with your thoughts.
You experiment with your 'powers' a bit. Hard to tell exactly how strong you are. You're not sure you could lift up a car, for example, but throwing around a person would be easy. Your reflexes are much better, too. You can switch between your deformed, fangs-out face and your normal face at will. You don't need to breath, and you have no reflection. There's no garlic to test, so you're not sure if that's still a weakness. A wooden stake, beheading, or fire- any or all of those might kill you, and you hope you never have to find out. If holy water exists- you're not sure. Would you still be able to visit churches? Impossible to know how many of the common vampire tropes are actually true.
When night falls again, you finally leave the graveyard in search of a pay-phone. You find one, and feel a bit paranoid looking around the empty streets, wondering if you're being watched. Ignoring your paranoia, you glance through the phone book trying to find some place that might have what you need. You find the address to a local butchery shop and decide to head over right away. Luckily, you know Sunnydale pretty well, so it's not hard for you to figure out where it is. You run through the empty streets at superhuman speed, and for the first time you feel happy about being a vampire. You feel strong, fast, powerful- like you could take on the world. It almost makes you want to forget this whole animal blood thing and find some REAL blood. The feeling begins to overpower your reason, and you..
[] Resist. You refuse to become a monster.
[] Resist. You still don't know enough about the supernatural. It's too risky to expose yourself.
[] Give in. You're not human anymore- you shouldn't let yourself be fettered by human morals. A girl's gotta eat.
[] Give in. You're strong and powerful now- who could stop you? It feels so good.
[] Something else?