Thanks for posting your query.
According to your description , buttock and thigh pain seems to be inflammatory in nature.
I advice you to give you rest to your left lower limb, take anti-inflammatory drug like motrin
1 tablet with food as and when required (upto 4 tablets daily) to reduce pain and inflammation and consult your doctor for thorough examination of buttock and thigh and rule out any infective cause.
Wishing you good health
Dr Saurabh Gupta