so late!!

af is a week late.. I've taken 3 digital test and all were negative. I was on the pill for 3 months, and stopped taking it when I started last month. guess I'm wanting advice on a couple things.. anyone else stop taking the pill and have a late period, or miss on completely? is there any way I would know if I'm going to ovulate or start my period first? I had taken some blue dye tests and they had bad evap lines,but after having 3 negative digital tests, I think it's safe to say I'm not pregnant.