Hi,
To be honest, I can't remeber how I was 3 months after Tamoxifen. I was tired but I think it was be due to couple of factors for me, a) tried fill in the LOST-TIME with my young children b) wow my life is back, let fit-in as much things I can c) I think the "pacmen" and "R-pacmen" still working hard inside my body (chemo & radiation - my body is still healing).
The good news is that I've been on Tamoxifen since Mar 2010 (so that is over 12 months now), and I am not feeling tired. I do take supplement with vitamin B daily. My side effect is dryness, and when I take a break from Tamoxifen (for reconstruction surgeries) and take it again, I get HOT flushes occassionally for the couple of month.
I guess everyone is different. If you are like me before, perhaps you might consider reviewing your daily activities, and it is okay to rest and chill. Also important to talk to your doctor regarding your concern.
Q: do you take Tamoxifen in the morning or before bed? (I take mine before bed)
check out:
http://www.bcna.org.au/network/groups/10661/blog/13936
Common Problem with Tamoxifen
http://en.allexperts.com/q/Oncology-General-Cancer-978/2010/4/tamoxifen-issues.htm
http://www.embarrassingproblems.com/problem/vaginal-vulva-problems/dry-vagina
https://beyondbreastcancer.wordpress.com/2011/03/27/managing-menopausal-symptoms/