I had my period on the 15th of feb, it lasted 5days and I had unprotected sex on the 28th, and used postinor 2 immediately, also used d 2nd tablet exactly 12hrs later. I then started bleeding on the 4th of march, it wasn t as heavy as my regular period but it lasted 3days. I immediately had a pregnancy test which was negative. I want to ask what bleeding is this and could I be pregnant