It's Hurting to Insert Something into the Vagina?

I'm 17 years old and a virgin, second time I tried to masturbate it hurt incredibly bad to try and insert what I be using into my vagina. It hurt around the hymen mainly/entrance, and yes, I used a lubricant. I didn't force, but I eventually got it inside and it hurt close to hell, I took it out.
What do you think the problem is? Lol, the above posters evidently don't understand it isn't your first time masturbating.
Just a guess, conceivably it's just sore. Sometimes that happen to me when I sleep in a funny position, or be too rough the night formerly.
could be many reason.. ask your doctor ;)