There could be several reasons other than the thyroid
for you feeling tired all the time.
1. A low hemoglobin
wears you out after little work; so you need to get a complete hemogram to ensure that your Hb is not very low. Iron levels can be done if the levels are borderline as that is a more sensitive test.
2. Vitamin B12
and folate levels - do get these checked and simple replacement can go a long way in improving your symptoms.
3. Vitamin D levels - do you get 30 minutes of direct sunlight everyday? If not, calcium levels go down making you tired. Allergies, recurrent infections are a problem with Vit D deficiency.
4. Constant runny nose, itchy eyes, lack of sleep at night are also problems of allergy
that lead to tiredness
. Do consult your doctor to get these checked.