It's not normal. In the side effects area in Pfizer's official documentation, you should consider ceasing Zoloft with the full knowledge and managed supervision of your doctor. It states it is a reason to be discontinued.
"What are the possible side effects of ZOLOFT?
ZOLOFT may cause serious side effects, including:
See “What is the most important information I should know about ZOLOFT?”
Feeling anxious or trouble sleeping
Common possible side effects in people who take ZOLOFT include:
nausea, loss of appetite, diarrhea or indigestion
change in sleep habits including increased sleepiness or insomnia
sexual problems including decreased libido and ejaculation failure
tremor or shaking
feeling tired or fatigued
Other side effects in children and adolescents include:
abnormal increase in muscle movement or agitation
urinating more often
heavy menstrual periods
possible slowed growth rate and weight change. Your child’s height and weight should be
monitored during treatment with ZOLOFT.
Tell your healthcare provider if you have any side effect that bothers you or that does not go
away. These are not all the possible side effects of ZOLOFT. For more information, ask your
healthcare provider or pharmacist."
"Patients, their families, and their caregivers should
be encouraged to be alert to the emergence of anxiety, agitation, panic attacks, insomnia,
irritability, hostility, aggressiveness, impulsivity, akathisia (psychomotor restlessness),
hypomania, mania, other unusual changes in behavior, worsening of depression, and suicidal
ideation, especially early during antidepressant treatment and when the dose is adjusted up or
down. Families and caregivers of patients should be advised to look for the emergence of
such symptoms on a day-to-day basis, since changes may be abrupt. *** Such symptoms should
be reported to the patient’s prescriber or health professional, especially if they are severe,***
abrupt in onset, or were not part of the patient’s presenting symptoms. Symptoms such as
these may be associated with an increased risk for suicidal thinking and behavior and indicate
a need for very close monitoring and possibly changes in the medication."
Zoloft on Wikipedia
Official Pfizer on Zoloft and Documented Suicide (p.43)
National Library of Medicine
FDA on Zoloft
Zoloft side effects and birth defects http://www.zoloftbirthdefectlawyer.com/