Pregnant?

I started using Glow a little over a month ago & we had sex every "fertile day" I had. My period usually comes on the 12th or 13th at the latest. Generally is always right on time. 

I've had no signs of my period coming like I normally do. Instead, my boobs have gotten significantly bigger & my nipples have been pretty itchy. I'm almost 4 days late so I don't know if I should wait longer to test or go for it? What do you ladies think?