Could I still get implantation bleeding AF due 9/13

Jazmin

Okay ladies I took a test this morning but it was negative I been cramping for the past week but I just wipe right now and notice CM and little stringy blood. Could I still get implantation bleeding since AF is due on 9/13 ugh I feel so frustrated and scared to start AF early. Every app is saying I should start on 9/13 last month AF started on 8/18