No period Neg test :(

Jodie
We have been TTC for 5 months and my last period was 23rd Sept..had very light spotting in Oct when I wiped but nothing else. I have got some cheapo tests on EBay but they all show negative and I am due on again today and nothing. Very mild cramp but nothing like usual..went to my dr he basically said come back in 3 months if your period still hasn't come. Worried something could be wrong as I have never ever missed a period bar my last pregnancy in 2011 and I am only 31 xx