I am now 10 days passed my missed period. I have not had any pregnancy symptoms and on the 3rd day of my missed period got a negative result on a home pt. Now on the 9th and 10th day of I am only spotting a light pink in the morning and nothing later in the day. I am also on birth control but worried it might have failed. What should I do?

I am now 10 days late on my period and this morning and yesterday morning I had a light pink spotting then later in the day had nothing. I am on birth control. On the 3rd day of my missed period I had gotten a negative on a home pt. What should I do.