Hi I’m 18 years old and I’ve had usually regular periods since I was 10. I used to get my period around the 20th-28th for five or so days, then my period started arriving closer to the start of the month for the past couple of years, probably due to the stress I’ve had over exams. My period this month is currently 8 days late, is that normal? And is it also normal if I suddenly miss a period? I am sexually active but I’ve always been careful.