Had a uterine ablation second week in november, had the normal discharge post procedure. have not had a period or cramps since until yesterday, some light brown discharge and cramps. is this normal?

Endometrial ablation is not always 100% effective in elimination of endometrial tissue, so some cramping and "brown discharge" is possible. See your GYN physician and ask about low dose oral bcp's, which should ameliorate the cramping and bleeding and avoid emotional withdrawal from ovarian hormones, which are still being produced despite the ablation.

What you are experiencing is normal and you are still early post procedure. There are various systems to do ablations and generally they will at least reduce bleeding 85% of the time but may eliminate it less than 50% of the time. You will continue to have cycles so it will remain possible to have periods.