Need a lot of advice....!

Ok I'm 16 days late. My next period is next week. I've had 2 BFN blood test. But I still think I can be pregnant. My periods are always on time, my breast are super sore, feel like I have to throw up all the time, sleepy all the time, my boobs even leaking & my vain showing a lot more then they use to. I'm not stressing at all. They only thing I stressed over was the doctor said that I might have PCOS. But they never tested me for it. They gave me some BC pills to start but I was a second opinion. I really want to see another doctor. They said the same thing with my DS. Then turned around and found out I was 6 weeks pregnant. I wonder if that's the case. What should I d???