Need Advice.

Hello ladies, I am a mother to a three year old son. He's wonderful. I am 21 yrs old. My issue is first the back story, after my son was born in Nov. of 08 I had the Mirena put in Dec. of 08. I had it till Oct of 11. I had to have it removed because it caused Pelvic Inflammatory Disease. It was about an inch below where it should have been and upside down. Since I have had my son I've had regular periods. Even after I had the IUD removed. Although after it was removed I suffered from massive cramps every month and major migraines. Well currently I am two days late on my period. I've taken two test, one at night that was negative and one first thing in the morning that was also negative. What are suggested next moves for me to make?