Late + BFN! What’s going on

My period always comes at 14dpo. Sometimes on the morning of 15dpo. Yesterday I had cramps and leg pain so I thought for sure it was coming. Fast forward to this morning all my cramps are gone, my boobs hurt, sore nipples, no period and negative test. What could be going on?! Has anyone had a positive test once they were a few days late? So confused! Tracked ovulation with opks like I’ve been doing for the past year, and without fail period always comes on 14 dpo. I count my O day as the day after my positive...could I have ovulated later than what I predicted?