Help please?!?!

So I've been TTC for over a year been pregnant but but had a MC. We started taking fertilaid for men and women about 2 months ago and I am now 20 days late on my period but all the tests are saying negative. No symptoms really.. Could I still be pregnant? Should I go to the dr? The one time I was pregnant it was the same way. I had a period February 1st and then found out I was pregnant on March 16th.. Any advice?