Strange cramps?

My periods have been coming every 27-30 days for 2 years now. I think they'd be considered regular. My period was due Nov 5th. It didn't come. I have had sharp, cramps that feel like period cramps from Nov 5th and everyday up until right now. It's weird because the cramps come and go throughout the day and night. Here's the thing..I have blocked fallopian tubes because of Endometriosis. I was told that chances of pregnancy were extremely low, if not impossible. What are other reasons that I would be experiencing this cramping? Why else could my period be late like this? Also, my boobs have been very sore and I've been very tired.

i usually get cramps a week before my period even starts. and my boobs hurt before i get it. you're probobly just late. it's normal to get your period late. it's usually not a symptom of anything. my period is late all the time

Low chances do not mean "impossible". Go out a buy yourself a pregnancy test.

It might be any number of reasons, try http://www.mayoclinic.com/health/symptom...
for a rough idea of what may be triggering it.

Here are two possibilities. When you first get pregnant, you have cramps that feel like you are going to get your period, but it never comes. Is there a chance you could have gotten pregnant. I have endometriosis also. I have two kids.
Another possibility is that your endometriosis is worsening. My cramps are all of the time now. My endometriosis is so bad I am having a hysterectomy in a few weeks.