I was recently switched from Toprol XL to the generic form of Nor...

I was recently switched from Toprol XL to the generic form of Norvasc. I have been on it for a little over a month now. I am feeling less tired although i do notice more frequent headaches and some constipation. I don't have any swelling yet but I haven't been on this medicine that long. But I am 2 weeks late with my period and am wondering if this new medicine has something to do with it. I have fertility issues so pregnancy is unlikely although not impossible. Has any other women had any other similar experiences.?I was never late or missed a period and now this is freaking me out.