Thanks for the query.
According to your description there is possibility of femoral hernia
Femoral hernia is protrusion of abdominal contents through the fermoral ring.
It is more common in females than males.
So you better consult gynecologist and general surgeon
to get examined and find out the actual cause of the lump.
As painful hernia can indicate complications like incarceration etc better to consult the doctor as early as possible.