What Causes Spotting After An Intercourse?

Im 26 my height is 5'2 my weight is 180lbs and i have a family history of diabetes...Ive had a dough like discharge for about a week or two but for the last two days there's been a red tint to the discharge, my menstrual cycle went off six days ago and i last had sex five days ago could someone tell me what this might be please?