I took these last night, they were immediately positive. I was not trying and it actually surprised me. When I calculated my due date it says I'm currently 3 weeks pregnant which is odd to me because the lines are so dark. This is not my first pregnancy but it's been years and it feels new to me. Does this seem weird? I'm worried about a chemical or something because it's so early. I've also spotted super pale pink and brown the past three days. I thought it was my period at first.