I did but since I am 50 assumed it was due to the change. Never even thought it might be related to the meds - but I am not taking it regularly anymore and my cycle never returned either - no complaints here.
However since I didn't start amitriptyline until 2 yrs after the tmj pain I can tell you that from the onset of my tmj pain, my periods did change, were not as frequent, no PMS. and lasted only 2-3 days - at that time I assumed the duress and stress my body was enduring affected the hormonal balance as chronic pain can affect various productions of hormones and chemicals, increasing some and decreasing others in response to the pain, not to mention the endocrin system is affected - adrenaline, etc. But it could also be that I was going through peri-meno at that point, I am not sure.