I don't have any advice to add to what's already posted, but did want to say that I commend you for giving this cat a home and taking the time to learn about responsible care and understanding their behavior. You'll both benefit from this.
She sounds like a very sweet cat. I was in much the same position as you when I adopted my first cat, Katie, many years ago. I'd grown up with dogs had no experience with dogs. As a small kitten, Katie's behavior surprised and frustrated me at times, but we made it through and she grow into an affectionate, fun, loyal companion. I've never run across anyone who thought black cats were bad luck. That's such a ridiculous, outdated superstition. I've heard that in some cultures, black cats were considered good luck. I personally find them to be among the most beautiful and mysterious of cats and hope to have another black cat some day. I just want to encourage you to continue to follow the great advice you're receiving here and be openminded and patient as your relationship with your cat develops. It's so worth it! Good luck!