feeling pregnant?

I see alot of women that say they just "feel pregnant"...what kind of feeling is that? any physical symptoms? intuition? really any answer I can get would be so wonderful. I've thought/been scared I was pregnant in the past but i just kinda knew I wasnt...but this time, I just feel different, my nips are sensitive, I have a hard time sleeping now even tho I'm exhausted, I get kinda dizzy sometimes, idk I just feel different. But I'm not sure if I'm pregnant or if it's because I've gotten myself excited and my body is just tricking me.