I got my period on feb 29th but we had unprotected sex on march 1st. He came inside of me- we thought it was safe. But then my period became very light spotting when it shoulkd have been heavy still. After my period a few days later around the 8th I started spotting but it only lasted a day. Now it is the 14th- I read you can take a test after 10 days so I took one and it was negative. Am I OK or should I be worried?