Ladies, I need your help.

Okay, so, I'm due on today, my periods have never been irregular, glow is never wrong and hasn't let me down. I normally come on in the mornings when I wake up, but, this morning I didn't. This has happened before but the times it has ive come on at either midday or evening. It's late now and I still haven't come on.
I don't feel like I normally do before my period either.
I am in a relationship, but its been long distance for two weeks. I've been feeling weird the last few weeks, more tired, been really forgetful. My blood pressure has gone up as well and my breathing a been funny. I've been getting lower back pains and dizzy spells.
I'm either pregnant or there'sjust something's  wrong with me. 
Am I too paranoid? Am I just looking for something to be wrong with me?
I don't know what to think or do, starting to worry myself tooooo much.