Hi, welcome to Scarleteen.
A few things, first: when something hurts like this has been for you, it's best to quit doing that particular thing. We also do not
recommend using anything for masturbation or any other type of sex that has something sharp on any end. This is dangerous because it could slip and you could seriously hurt yourself.
Sometimes it can take awhile to figure out what feels most pleasurable for you and you're most comfortable with doing -- this is normal, and figuring it out can be fun and satisfying.We have an article here on D.I.Y. Sex Toys (Self-Love Edition)
that I recommend you read. Let me know if you have any questions or comments.
Additionally, I'm curious if you felt pleasure from masturbation at other times in the past and this is a new thing, or if it has never felt good for you? Are you aroused when you masturbate -- not only physically, but mentally as well? Arousal is an important step in the pleasure process.
Here are more resources on that topic:Going Solo: The Basics of MasturbationWith Pleasure: A View of Whole Sexual Anatomy for Every Body