According to your sign and symptom you are suffering from severe weakness from a viral disease.
Any viral disease infect the all system of the body like gastrointestinal system musculoskeletal system and immune system so it weaken the body so much and weakness is the most prominent symptom and it persist in the body after infection.
Next Steps
for prevention of this weakness You did follow correct lifestyle like take sufficient amount of water as 4 to 5 litre water
and take balanced diet and
do yoga and meditation.
Generally it take one or two weeks to recover from a weakness if you follow the correct lifestyle.
Health Tips
please keep positive attitude to fight any disease and any problem of your life.