Is this a faint line? This is all I'm getting!

Nicole • Happily married to the man of my dreams. Mom of 2 girls, Elena and Esme, and 3 👼👼👼 .

I am now 2 days past my period due date, and have been taking tests every day for 4 days(different brands too)and I just keep getting these very faint lines on them. Shouldn't they be getting darker? Am I possibly not pregnant? Or am I?