Late period

My period is always on time only ever deviating by a day (I double checked my last year and a half of glow records to confirm this). This month however I'm currently 2 weeks late. This has never happened in the 11 years I've had my period and I don't know what is going on.

I've taken 4 pregnancy tests spread out in the last 2 weeks starting a couple days after my period was due to arrive and they were all very negative. My husband and I had not had unprotected sex.

I also had 2 weird over emotional pms days about a week before my period was due to start which isn't common for me. And in the last couple days I've noticed an increase in the amount of times I need to go see disproportionate to the amount I drink.

I'm planning on seeing a Dr if I miss my August period too because this is so unusual for me.

Has anyone experienced anything like this before?