Bappy,
Sending prayers your way.
What are your iron levels?
Do you have a spleen?
Fever in thalassemia always need to be investigated and treated. High iron levels, as well as splenectomy can put thalassemia patients at risk of complications from infection. I suggest that you seek medical help. I believe that you will be well, but it is especially important to get help.
Fever and aches can be a sign of a cold or the flu. It may be a good idea for doctors to investigate the source of the infection. If it is determined to be cold or flu - and symptoms are not improving it may be a good idea for them to begin antibiotics and antivirals.
sending you my best, and lots of prayers,
Sharmin