I am seventeen years old and a few days ago I experienced a small amount of red spotting that did not continue, and it was exactly one week before my period is scheduled. I'm on noregestimate and ethinyl estradiol pills, and last month I took two of them aproximately eight hours late, but this month I have taken them all at just about the same time of day. I have sex without a condom relatively frequently. I haven't noticed any other signs of pregnancy, but I do have a cold and I have been particularly stressed lately. Is it likely that this is implantation bleeding, or could it just be illness and stress? I am very nervous about this, although I have a plan for how I would deal with a pregnancy if it occured. Relpies are appreciated.