Skipping Ovulation ?

Just wondering if this has happened to anyone else. We have been TTC since June and nothing yet. I've gotten a bunch of tests done recently with 2 different doctors and everything comes back normal. But in December I skipped ovulation and then got my period late 10 days then January I ovulated (no baby) got my period on time and now come February I did not ovulate and my period is late again and took 3 pregnancy tests and nothing :-/