You should go to the doctor asap. With my first it was hard to detect because i had low hormones which can have its affects. The doctor will do a blood test to confirm ur pregnant. And tell u what todo if you are. I am preganant again it took a couple of negative test before a positive came out. Try taking the one that shows how many weeks you maybe they are more sensitive.
Maybe you should go to your doctor an let he/she do a blood test