I am very concerned that I am pregnant, and I NEVER want kids. Maybe some day I will change my mind but it's not likely. So here it is:

I started the Pill in August. I have never missed a pill, I may have taken it a few hours off but nothing major. I have experienced typical Pill symptoms such as breast swelling and tenderness, bloating, some headaches, etc and my periods have been very regular the last two months so I have assumed that the Pill was doing it's job. I have just started my 3rd pack of the Pill after my last withdrawal bleed. On that day of the 1st pill of the 3rd pack I experienced some light spotting for maybe two days (could this have been implantation?) Since then, for the past week, I have been having terrible lower back pains, some cramping, leg aches, and headaches. I have had "unprotected" sex maybe 3 times since i have started the Pill, but also used withdrawal method.

I am very concerned because I have never felt lower back pains like this right after my period for such an extended amount of time, or constant annoying headaches. I am really, really, really, worried that I may be pregnant even though I am on the Pill and I had my withdrawal bleed, because everyone says it is still possible. I guess I shouldn't have assumed the Pill was working and used a condom too. I feel so dumb. Please let me know what you think. I am planning on taking a pregnancy test very soon, but I want to wait till the end of this week.

What do you think the chances are? I keep trying to tell myself it's all in my head, but my symptoms tell me other wise!

Thank you for your time.