I have MH problems including Depressive Disorder; been under quite a lot of pressure in my work & personal life over the last 4 years...
A few months ago my period (which normally arrived approx 24th each month) was nearly 2 weeks late - it was worrying because i'd not had sex in the past year!
I was very stressed & anxious at that time for other reasons; then worrying about my period too added extra stress.
Then my period finally arrived & i was so relieved - now they are regular again but arrive approx 2nd of each month.
I got my bloods checked - hormones are fine; & i'm not peri-menopausal (i'm 36 & have a first cousin who got the menopause age 33). I got checked for any other physical health problems by my GP but was fine luckily.
I have had 'Disassociative' physical health problems (basically health problems that are real but have a psychiatric cause rather than an organic, physical cause.) So it seems rational to assume that it was the extra stress & anxiety that month which caused my period to be late.
I'm very relieved - despite the hell of PMT (which causes extreme paranoia & irrationality, depression & agitated behaviour for me) - i'm happy to have periods because it means that when i'm well i can still meet a nice man hopefully to have a baby with.
OP - i recommend you do the same; get all your hormone levels & other bloods checked by your GP, have a physical examination & if nothing is found to be physically wrong then it will put you at ease.
Meanwhile try to relax if possible because it could well be anxiety affecting your menstrual cycle.
Your GP is always the first person you should speak to with any health problems; do change GP if you feel it's necessary. A good GP will understand your worry about your periods.