Penny, have you reported this to the doctor? I don't believe stopping tamoxifen would start up your periods again. It's not the tamoxifen that stopped them; it's the chemo. It's possible to have periods again, but as you said, extremely unlikely at your age, and 3 years later. This doesn't sound like a period, especially if you've been bleeding for 2 weeks; might be from another cause.... I'd call and make a doctor's appointment, see if you can get this taken care of. Best of luck to you- PJH