Late period, negative pregnancy test?


My period is 15 days late according to this app and others. Since coming off the pill a year ago I’ve not been more than a week late so obviously I was very paranoid I was pregnant. I took a test a couple of days after my period was supposed to be due and it was negative. Took another over two weeks after my period was due and it’s still negative.

So I’m just wondering is this something I should go to the doctors about or wait it out? I’m quite scared and confused