Should Eltrocin Be Continued Or Discontinued For Tiredness And Delayed Periods?

Dear Doctor,
I am Thanima, 25 years, mother of a 15 months old male child. During the pregnancy of this child, I was undergone thyroid function test and advised me to take Eltrocin-50 mg once daily. Since two years I was on this medication and due to general tiredness, doctor did thyroid function test again, that shows a value of 1.43 ng/dl. The Physician told me that continuation of the medicine Eltrocin is responsible for the tiredness and advised me to stop the intake of medicine Eltrocin. It was stopped two weeks ago. Again I felt tiredness, non arrival of periods. So I consulted a gynaecologist and tested for pregnancy which showed negative results. The Gynaecologist advised me that the problems are due to the stoppage of medicine eltrocin and advised to take it again. I am confused. Which advise I need to follow? Please advise me.
Thanima
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