Thank you very much.
I would consider few causes that might be responsible for your symptoms.
First of all, exhaustion, excessive sleep and being over weight --- suggests hypothyroidism (a condition in which the thyroid hormone levels are reduced below the normal range in the body).
You might already had a thyroid test done, but its important to note that different labs have different reference ranges for TSH--thyroid test (usually 0.5 to 5.5); but recently new guidelines for the upper level of TSH have been set forward. The new upper limit of TSH is 3 as per AACE (American Association of Clinical Endocrinologists). Many doctors are not aware of this, so if you have a Thyroid test done, please review the report and discuss with your endocrinologist. If not already done, you can ask your doctor to order the test.
Prolonged sleeping spells associated with unrefreshing sleep can be due to Obstructive Sleep Apnoea Syndrome as well as Narcolepsy.
You can read about both of these by clicking the links below:
Depression may also cause excessive sleepiness and tiredness.
You should try to have exercise daily, and eat plenty of fruits and veggies.
Co-Enzyme Q-10 supplements are also helpful in this situation.
Get back to your doctor and discuss all the details i have mentioned so as to chalk out further management plan that suits best to your needs.
I would have been worried too if i were at your place but let me reassure you that this is a treatable condition and carry a good prognosis with appropriate management.
Wish you good luck.
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