levels should be below 3.
Ideally you must be on thyroxine
hormone as that will be sure shot method to control your thyroid
There should not be any fear in getting your TSH checked.
Uncontrolled thyroid will always lead to irregular periods
and will also cause problem in conception.
Don't be afraid of it as this is a very common problem and becomes completely alright if proper thyroxine hormones are taken in guidance of the doctor.