delayed menstrual period on althea

hello. I'm really, really bothered about my condition now. I used to have irregular cycles before. like having period after 3 months. but then, my period became regular since 2 years ago and I was happy and relieved. But during this year, my last period was last October. and then some stressful events happened during the next month which I associated to be the reason why I didn't have my period last November. But still, I went to my OB. She prescribed me Althea. I finished using it for 3 weeks now. This week was my pill-free week and on the 2nd of January 2010 (saturday) I'm supposed to take althea again for 3 weeks. Well, that's what my OB told me, to take it again with or without menstruation after having a one-week break from it.

Should I follow my OB and take another cycle of althea or should I just drop it and check if I'll have my menstruation even without having the pill?

By the way, I'm not sexually active though so there's really no harm for me if I stop the pill or not. I'm just using it because of my delayed menstruation. But based on my observations though while I was on the pill, I'm having mild to moderate cramps and backache. is it normal?

Thanks in advance! happy new year people!