Last week my girlfriend had a dysmenorrhea and every time she had dysmenorrhea has a 3 weeks interval and now she havev a dysmenorrhea and her vagina is aching and her boobs.

She has painful periods?

Yup

Has it always been this way for her?

Okay, I am going to need more information in order to help you.

Are you concerned about pregnancy?

Has she missed a period?

Are painful periods common for her?

How old is she?

Yup!

She's 18, regular menstruation, a virgin lol

Look dude, you are going to have to give me more info than just a "yup" here and there.

What are you worried about? Can you give me an entire paragraph as to what you are concerned about?

I can't answer you based on just a "yup" or a "nope."