Talk to Gynecologist on Vaginal Pain

I am having vaginal from past few months. During my periods the problem starts and goes for 2 to 3 weeks . my vagina and the whole area around it starts to itch, and sting with a lot of pain if i touch it. It gets unbearable. My sleep is effected and its very painful. After I take my,clean bath I start applying Vaseline to make it moist but it hurts a lot. It stings too. If I itch it even very softly it hurts a lot.. The Vaseline doesnt help. I even applied canestene ointment. It helps while that on. But then it start,the same. And it take 2 to 3 weeks to get better. By the Tim it gets better I get NY next cycle . Please tell me what I should do. Should I get it shown to a doctor or what do u suggeat