So i started taking the pill this month on the 7th which was when i started my period. About 2 weeks later on the 20th and 21st i had unprotected sex with my bf. He finished inside me both times. Well i noticed that after the 21st i noticed spotting/light bleeding. And its been like this for the past 3-4 days now. I noticed that the spotting started on the 22nd and its now the 25th. Is the implantation bleeding? Or is it because of the pill and my body adjusting to it? How long will it last and should i be concerned of pregnancy?