Welome to HCM
We understand your concerns
From the description the lump seems like an abscess
which is quite normal in every sense. Pus and blood and pain are part of abscess formation. Clean the area with warm saline water three or four times daily and it will be cured.
It is wrong notion that abscess should not be in such area. Abscess forms in areas where infection due to unhygenic condition takes place and also below hair folicles and sweat glands. Please consult a GP if symptoms persist.
Wish you speedy recovery.