There's this girl I like but she says she wants to make sure of how she feels for me. And now she says she can't love me because I'm too emotional and I get moody, so I don't know what to do. Any advice?

I'd recommend you get to know her better. But before that, get to know yourself. You have to understand what she meant by "emotional" and "moody. For example, it might mean that you are a little too clingy. On the other hand, it might be literal and mean that you are too intense with your emotions when you're around her, and that for you and her to be together you might need to act a little calmer. Become a close friend with her (if you aren't already) and, of course, don't try to change yourself for her. Emotion is a strength, and if she thinks that who you are already isn't enough, then she doesn't deserve you for who you are.