Your symptoms are most likely caused by underactive thyroid gland, a condition known as hypothyroidism.
You can have normal thyroid gland hormone levels (thyroxine), slightly high serum TSH concentration, and still, experiencing symptoms of hypothyroidism.
That's why you should be tested for T3 levels, TRH concentrations and for specific antibodies, known as antiperoxidase antibodies (autoantibodies).
Conditions that have similar symptoms with hypothyroidism are chronic fatigue syndrome and fibromyalgia, and must be taken in consideration when diagnosis of hypothyroidism is made.
Weight gain, depression, mania, sensitivity to cold, fatigue, panic attacks, bradycardia, tachycardia, high cholesterol, reactive hypoglycemia, constipation, migraines, muscle weakness, cramps, memory loss, infertility, coarse, brittle, strawlike hair, hair loss, dry skin, dry eyes, swollen eyelids, dull facial expression, hoarseness, slowed speech and movements, difficulty with concentration, red palms, itching, hives (solar hives, due to sun exposure), swollen legs, and other are all symptoms of hypothyroidism.
The antinuclear antibodies (ANA) are present in 1/3 of patients with autoimmune thyroid diseases, Hashimoto's disease, the most common cause for hypothyroidism.
Also, the frequency of rheumatic diseases seems to be higher in patients suffering from autoimmune thyroid disease, and initial evaluation and a regular checking for rheumatic diseases in patients suffering from ATD are usually recommended.
Best wishes!
Marija