Would Any One Help Me Out?

Now, the other morning, about a week ago if that, i noticed this pain in my , and on my left there is a big hard knot on the inside of my and its painful, and my are real sensitive, And They Will Randomly Start Burning And Tingling does anyone have any idea what it could be? Im Seventeen ually Active And Im Not 'On The Rag', Or Gettin Ready To Start My Whole Hurts And Now The Right One Is Startin To Hurt I Dont Necessarily Know If Its A Knot Anymore Because My Whole Is Firm And Hard, Both Left And Right Ones Are. Any Idea?