Cramping help

Jessica • Wife💍 Mother of 4! Craft boss!! http://www.instagram.com/jessicaann1115 Www.instagram.com/gorjesscreations
I have been having camps in and off since cycle day 12 I am on cycle day 16 what could this mean? I normally get a positive opk on cycle day 12 but i haven't tested this month but I never have cramping this long has anyone else had this problem?