What could be going on?

I'm on cycle day 23. My cylces are usually 30 days apart. I usually ovulate around the 4 th of each month. I am using the clear blue digital opks. I tested on the 4th and it came back no lh surge. I didn't test the 1st, 2nd, or 3td of this month and I have been testing the last week or so and getting no lh surge and for the last 4 days my boobs have been sore and o have been nauseous. On the 6th is when my boobs started hurting and I started cramping in my stomach which usually is what I do when I'm about to ovulate but the test showed no surge. So what could be going in? Could have missed my lh surge?