Brief Answer:
Please see detailed answer below.

Detailed Answer:
Hi and Welcome to "Ask a Doctor" service. I have read your question and here is my advice.
While it is necessary to regularly Chek for your thyroid status, certain of the problem you have may not be related to your thyroid. The following points are worth noting.
1.The lethargy, low feeling and aches may be related to thyroid ( low thyroxine), and I understand we should Chek the TsH level anyhow. Once the TsH is normal, your thyroid drug are optimum and does not need any adjustment. If there was any problem in TsH, we will adjust accordingly.
2.However the shortness of breath along with cough may indicate a respiratory problem rather then the thyroid drug. Specially if you had pneumonia twice before, So I understand it may be related to the chest problem and should be assessed. A number of chronic lung conditions may cause shortness of breath and cough. So I a recommend we should not put it to the the thyroid, and should see a respiratory doctor for proper assessment. This is necessary in context of previous pneumonia, and the persistence of symptoms.
3. The body aches and joint pains are not specific, may be associated with the either of thyroid or respiratory problem or to none, .If there is no swelling in joints and no stiffness, I would recommend to take some. Vitamin D along with calcium. I hope it would be better. Use paracetamol for the pain for the time being.
4. Please try to avoid taking to many pain killers like disprin and mortan etc. As they may cause stomach problems. Use paracetamol regularly instead. Use mortan only if needed above paracetamol.

Hope this answer help you understand your querry. Please feel free to ask if you have any further questions or concerns. I will be glad to answer your questions.
Kind Regards Dr Mahboob Ur Rahman

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