Spotting for 2 weeks

About 5 days before my expected period I began slightly cramping and spotting. It quite for about 2 days and then started again and has continued for about a week and a half (only one other day of mild cramping). My normal period never did start. According to my app I’m 9 days late now. What else could be the cause of this?? I haven’t tested yet, because honestly I don’t want to get my hopes up that it could be implantation bleeding and then have my hopes crushed again.