I just had my son on 6-18-15th and had my first period on 9-6-15 to 9-10-15 then had my second one on 9-22-15 to 9-25-15 and I was supposed to start again on 100-8-15 but never did I went to the ER and had a pee test done but it was negative. However I have had four kids and I have never had a pee test come up positive until I was 16 weeks pregnant or longer. I'm if I should go get my blood tested or if I should just wait.