Hello,
I have gone through your query and understand your concern.
As your pregnancy tests are negative, Pregnancy a common cause of missed period is ruled out.
There are plenty of causes for Missed periods.
As you are taking medications ( Cymbalta) for
depression or anxiety, I suspect you are a depression patient.
Other than Pregnancy, Stress or anxiety or Depression are the common causes for missed period.
Other possible causes are
weight loss, Severe dieting and poor nutrition, obesity.
It can also be caused by Hormonal imbalance at times.
You have rule out any Poly cystic
ovarian disease by doing an Simple
ultrasound abdomen and pelvis.
Rule out
hypothyroidism by checking thyroid hormones.
Sometimes periods are missed for no apparent reason, and this does not mean anything serious is wrong.
Hope this helps.
please write back for further queries.
Wishing you good health.