Is there a way to delete a period? Could I possibly be pregnant?

According to calendar, my period was suppose to start the 2nd of July, and end on the 5th, but I haven't started it yet... I'm late... My periods have always been irregular. But they have been somewhat regular for the past 2-3 months. Anyway, I'm still waiting to get my period but I can't delete or get of the period that I currently "had" it congratulated me on ending my period for that week but I didn't even get it! 
I've been cramping a lot too. 
What are some early pregnancy signs?