What's going on?

So. I'm two days late on my period. No cramps, not a sign in the world I'm going to start. I took 2 test yesterday and both said negative. I'm 13 do and finding a lot of discharge in my undies. What's going on? Anybody expierence anything similar? I'm lost and confused. We aren't necessarily ttc but if we are pregnant why isn't it showing up and why is my period not here?