TTC BABY #2

Breanna • Marine Wife 💍 8/6/14, 2year old boy👦🏾8/17/14, angel baby👼🏾3/7/16, angel baby👼🏾9/1/16. RAINBOW BABY 8/14/17👶🏾
My son is 15 months old and he wasn't planned. And now I am trying to conceive baby number 2. 
I have been showing signs of pregnancy for a few weeks but the tests say negative. I go in on Wednesday for a blood test. 
What are some fertility teas or vitamins I can take. 
I NEED HELP!!