Hi, i am in the same situation as you at the moment, it's been 87 days today since the start of my last period. I have never missed a period before.
We started
TTC and i haven't had a period since.
I went to the doctors and they took some blood tests as all my urine tests were negative.
The blood tests came back clear, so the doctor has booked an ultrasound scan for 8th january to check everything is ok.
There is no reason why i would miss periods as this has never happened before...typical it happens just as we start
TTC.
My advice to you is to contact your doctor and ask for an ultrasound scan...they pick up everything, so will hopefully put your mind at ease.
Good luck with everything xx