I am 39 yrs old. Have had my tubes tied since the birth of my last child, 11 yrs ago. Periods have always been 5-7 days. Been using a period tracking app since 2013. Started 4 days early and am still going strong on day 13. I know I need to make an appt. What are some reasons for a sudden change like this. My stress levels are always high. I work 3rd shift and raise my 3 children on my own. I've googled it and got everything from pregnancy to cancer.