hello, I was asked by a doctor to start taking the contraceptive pill due to irregular periods about 3 weeks ago. I started taking it exactly 3 weeks and 2 days ago, without starting it on the first day of the bleeding. Because my periods were irregular I started taking it on a random day.Today I had unprotected sex and realised it had only been 3 weeks since I started on the pill. I was wondering if I should be worried about a possible pregnancy since the pill could not have been effective for the last three weeks. The fact that I didn't start it on the first day of the cycle is what scared me. Should I consider the morning after pill? Or has the pill been effective. Thank you