Ob-Gyn questions? Ask a gynecologist online.
you can rely this negative result as it is done in proper time and HPT is highly sensitive and accurate.
I not does not matter when you ovulated.
As the urine test is negative you are not pregnant.
This may happen due to imbalance of sex hormones, stress and strain,thyroid disorder.For restart of your period you can have withdrawal bleeding by progesterone.