Why does she hav painful menstrual cramps now when she had period 2 weeks ago. usually irregular period, every 2 months. did sex in morning cause this?

See details: She is having abnormal uterine bleeding caused by a lack of ovulation. Without ovulating and normal hormone function, endometrial tissue becomes unstable and bleeds unpredictably. In addition, these irregular cycles are associated with a higher risk of endometrial abnormalities over time including precancerous and cancerous changes. She should see her gynecologist. Prevention is the key.

Pelvic cramps/pain: Though menstrual cramping is a very common cause of pain during the period, other things can cause very similar pain during other parts of a woman's cycle. For example when the egg is released from the ovary there can be sharp pain for a few hours. And vigorous sexual activity can cause uterine cramping. Also ovarian cysts can cause pelvic pain. Be sure to follow up with your gynecologist.