Hi there bz123, and welcome to Scarleteen!
Something I think might be really helpful is for you to read
With Pleasure: A View of Whole Sexual Anatomy for Every Body. This article talks a lot about the different factors that contribute to the pleasure response - especially the huge role that the mind plays. If we're not feeling aroused, relaxed, and ready, something entering the vaginal canal isn’t going to feel very good at all. (Especially because during arousal, the vagina expands and the glands produce lubrication - without it the friction is pretty painful and not fun at all.) When you masturbate, do you spend a little time thinking about people or things that turn you on?
But also, there are lots more ways to masturbate without putting anything inside of the vagina. It could mean rubbing or massaging the labia, the clit, the vaginal opening, or any other parts of the body. Really, anything that makes you feel good is fair game, as long as you're not hurting anybody. (And, I might add, the more you do it, and feel comfortable with yourself, the better it gets!)
While you're reading things, I would really suggest checking out
Innies and Outies: The Vagina, Clitoris, Uterus, and More because it has more detailed drawings and explanations of the different parts and how they work together to make us feel what we do. Also,
Magical Cups and Bloody Brides: Virginity in Context gives some background about the concept of "virginity" and how many different values and meanings are placed on it - it's a real eye opener.
Also, I would highly reccommend
Ready or Not: The Scarleteen Sex Readiness Checklist, which can often help a lot of folks in figuring out how they're feeling about sex and whether or not it's something they're comfortable with doing. There's a lot of pressure out there to have a lot of sexual experiences as soon as possible, but the truth is, what you do with your body is a personal decision, and one that you should be able to make at your own pace. Getting to know your body might make things feel a little bit more comfortable and less scary, but you should know that there's nothing wrong with taking things slowly!