First pregnancy

Just found out I'm pregnant. I have an appointment Scheduled for the end of the week but I'm just confused. My last period started December 27th, so I haven't even ovulated yet. I've taken tests before that have come out negative but these came out with both pink lines extremely visible. Not even a slight faint line. So now I'm just worried that I might have miscarried or something may be wrong, I don't feel sick or anything. Slight discomfort here and there in my lower abdomen but until I get some answers on Friday, is it possible I'm just reading into it too much? Can you test positive SO soon or is it possible we conceived earlier?