Hi thanks for your question.
You had a swelling on back side of your leg below knee joint,which increased in size and become more painful following removal of ingrowing hair.
Most probably this is swelling is folliculitis
that is infection of hair follicle.
This folliculitis has changed into cellulitis
.(inflammation of surrounding tissue)
All that you need is a course of antibiotic and analgesic
anti inflammatory drugs for a week.
If abscess forms within swelling in due course of time it will need drainage
Folliculitis don't need steroids
neigther local nor systemic.
You can discuss with the consulting physician regarding the need of steroid.
Hope i answered your question.