Potential trigger warning: dentists/needles

I have an upcoming dental appointment, and I can choose between being knocked out for it or just a local numbing. Most of my anxiety comes from the needles, but I'm also scared of just general pain, which wouldn't be a problem if I was knocked out, however, I'm afraid that if I get knocked out I'll wake up in the middle of it, &gt;!throw up, !&lt; and just general needle-being-in-my-arm fears. Is one any better than the other? Or is there anything I can do to stop freaking out over needles?