4 days late. 3 days late.

I have a period Diary that I use, and I use Glow. Well, my P.D. Tells me I'm 4 days late. And glow tells me I'm 3 days late. I'm a hypochondriac, and for those who don't know what that means, it means that I could think about it and have the symptoms of it, when I really don't have it. 
​For the last four days I've experienced cramping, and my nipples will hurt every once in awhile. I can touch them and they won't even hurt. No neausea, my boobs don't feel like heavy, i can't tell if they're getting darker. I'll get light headed if I get up too fast. I've been a little emotional, but not too emotional. 
​I've tried getting pregnant in the past, with my ex boyfriend. But nothing ever happened. I always followed what to do, but I stressed about it, now I noticed I was close to my period day, and I still haven't gotten it. I don't want to jump to convolutions because I've done that in the past, and have been disappointed. Does anyone know what this is?