Noted your specific history about flu
like symptoms, pain in hip
and groin area, can not stand straight.
The commonest causes I can think about are as follows:Sprain
at the muscles attached to the pubic bone causing typical symptoms and accentuated by viral infection.
Any disease related to hip.
node related problems.
Fascitis and so on.
This can be diagnosed properly by the following ways:
Clinical examination by a doctor.
Relevant investigations like MRI of the affected area and hip joint.
Relevant tests of blood, urine and stool.
All these will lead to a proper diagnosis and have a proper plan of management.
Till then take an anti-inflammatory with pain killer properties like Ibuprofen
as per your weight and have complete rest to the area.
Hope I have answered your query. Let me know if I can assist you further.
Dr. T. Chandrakant, General Surgeon