Pee-on-a-stick-aholics please read and help!!!?

I have been taking a test almost every other day and It's been 40 days since my last period. I had very light brown spotting on 8/13-16 but no period??!! Could I still be pregnant since I havn't gotten a BFP yet? Has anyone else been late and taken a test one day then a couple days later gotten a BFP? How late was it!? Thank you!