Late period, but probably not pregnant

im so perplexed...im 40, and in all the years i have gotten my cycle, i have NEVER been late...never...i have been early, but never late..

well, i have been getting longer lasting, periods early since november (its now may) and my last one , i spotted an extra 4 days! (it went on for 9 days) and i was concerned...

well, now i am a week late , its possible i am pregnant, but i doubt it. I have not had unprotected sex since my last period..
could it be hormonal change?

I went to a doctor and had bloodwork done and was told i am NOT in menoause, so i dont understand it.