Welcome to HCM,
You are having Hypothyroidism
and I am sure you must be taking Thyroxine Your symptoms tiredness and irregular period are possibly due to inadequate dose and may be associated anemia.
Please visit your Physician and check your Complete Blood count
and FT3,FT4 and TSH and if TSH is high then dose of Thyroxine needs to be increased and if your Hemoglobin
is low then proper vitamin and supplements need s to be given.
Once you become Euthyroid and your symptoms persists then it is possible you have depression associated which can be treated with Psychotherapy
or mood elevator if required, with consultation to Psychiatrist
It is good that you are busy with hobbies.
Please wait for your test result once your treatment is started you will improve be optimistic .
Please take care.