What Causes Unusual Bleeding And Headache After Intercourse?

girlfriend usually has her period for 7 days normal flow and 2 days spotting however this month she only got a 3 day period with a heavier flow and only 2 day spotting after that. she has been feeling weird feelings in her stomach, having bad headaches although she has always had headaches in the past, and now a week after her period ended, she randomly started bleeding from her vagina