What Causes Pain In Vagina And Abdomen After Putting A Tampon?

I have worn tampons my whole life but in the last year after i put a tampon on i get sharp stabbing pains in my vegina,lower stomach thatshoots all the way to my rectum ...even after i take the tampon out (which is unbareable) the pain continues and seem more intense while sitting ....what can this be ?????