You have Hypothyroidism
and was taking Thyroxine
Treatment should not be stopped, it is good that you realized,I presume you must have not taken treatment for sufficiently long time. Hence you started getting symptoms of hypothyroid state.
You must understand severe complications like myxedema coma
Please do not worry it will take some time before your all symptoms improve if dose is not tolerated then it can be started from low dose may be 100 microgram/day .
This can be increased in 3 to 4 week after rechecking your TSH level
We should check if there any other cause like anemia for your symptoms and it it is there it must be treated.
One must watch for osteoporosis
during long term treatment of Thyroxine as you are taking this drug for more than 20 years. This is even more important in postmenopausal women.
You can ask me at http://www.healthcaremagic.com/doctors/dr-akhilesh-dubey/63985
Please take care
Dr. Akhilesh Dubey M.D.