Very late period. Help!

My period was suppose to start on the 17th of this month so I'm 10 days late. My cycle always comes 2 days before or even a day before it's been like clock work. My nipples have been hurting for almost a week or a week straight now , and I always get this cramping that hurt for minute and go away also I get nauseated. I was pregnant before and had a MC at 5 weeks , but I didn't get a positive result till I was 4 weeks that was with blood and urine test. I don't know what to do. Somebody help.