Late period - ugh

I just want to vent. I’m usually a 29 day cycle. I am now cd46. 17 days late. I have never skipped a period, so I’m freaking out. I don’t think I’m pregnant because the last time I had sex was late sept and I’m pretty sure we used protection. I got my period oct 5 as normal, ( but I can’t remember if i ovulated in October) and come this month November 2 when af was due, she made a no show and hasn’t since. I’ve taking a number of hpt, different brands and they are neg. which is what I would assume... but AHHHHH!! Wtf. It’s frustrating not knowing what’s going on and what’s causing this.

I just turned 37, so I’m worried it’s premenopausal, but so quickly? Has anyone had a regular period and for no reason skipped? Or does this usually result in some kind of medical issue? I have a dr appt tomorrow and I’m really nervous!