No tests at present...
At the outset, you need to know that ESR
is a non specific marker. A specific cause cannot be determined based on ESR alone. Generally it is followed up with other tests to isolate / diagnose medical condition. However marginal elevation of 24 needs no further testing at this point.
You probably are recovering from flu
infection. Headache, myalgia
, weakness are common post viral symptoms. It takes couple of weeks before you will feel better. I encourage you to drink plenty of water and have fresh fruits and vegetables. You can repeat ESR and complete hemogram if you continue to feel unwell after 2 weeks. Your doctors can take a call to investigate further based on your symptoms and the repeat ESR value.
I hope this information is helpful. Let me know if you need clarifications.