I am really f****** confused. Please help.

So on here its telling me I am going to start my period yesterday, it never came. When I look online every website I checked said o should have started my period around May 22ish. I haven't, like I said my last period was April24-30, and glow says I was ovulating when I should have been having my period according to every other website. What am suppose to do, keep waiting until I do start or buy a pregnancy test just to be sure.