Skipping periods?

Katie

So I had a miscarriage and had to have a D&C; and at my follow up appointment my doctor gave me birth control. I take microgestin fe 1/20. I haven't had a period since before I was pregnant, which now has been 5 months. I've been on this birth control for 2 months now and still haven't had a period. Should I be worried and call my doctor or has anyone else had this happen? I know I'm not pregnant because I test regularly just to make sure.