Advice needed please!

Hello Everyone, i need all your worldly advice. I have been ttc for 3 months but this is the 2nd month i have been tracking my ovulation with a ovulation kit (using clear blue digital) i have been reading that you dont use your first morning pee to test however the instructions in the kit state your first pee after your longest sleep! I have been doing that but my last  3 tests have been negative. What do i do? I am scared that i may not be ovulating. Can you please help??