<a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> predicted my period to come on the 19th but it hasn't yet. I had protected sex on January 1st. I haven't had any pregnancy symptoms, the only thing I've noticed that's a little off from my usual PMS symptoms is that my nipples are sore. Should I test? When should I? Why is it so late?