I have been having abdominal cramping mid-cycle. Does this mean my bc isn't working?

Not necessarily . If you are taking the pill as prescribed, you shouldn't be ovulating. The pain could be caused by multiple things. I would double check that you aren't taking any other meds that could interfere with your pill, especially antibiotics. If the pain continues, see your doctor for an evaluation and likely an ultrasound.
Just your cycle,, . This is likely just your cycle. It might help to adopt a healthy diet with lots of protein and fiber from fruits and vegetables, as it would help your digestion, keep your iron up, and could stop the cramping. Best of luck.