... about two months I did not like the Depo shot so with doctors help I switched back to Aviane , I'm now on my 2nd packet since the switch I'm on the 4th week on my 3rd sugar pill and I still have not got my period ,I've had slight breast tenderness but only for a day or two. before I would always get my period when I was on the pill during the 4th week.I haven't missed no pills at all but I do have unprotected sex, should I worry? Am I pregnant? HELP!!!