Confused about what happen...

Ok so from the top...my first day of my last period was dec 31st (Lasts for 3 days), then it was January 31st, my app says February 16 is my ovulation date. Then on February 18-19th I’ve had a “Menstruation” I’m not sure if it was implantation bleeding or a period. Now March comes and no period as of March 10th