The cause of recurrent infections in your case could be related to diabetes.As you are having numbness also,so diabetes which is an important cause of numbness in the peripheries has to be ruled out.
Secondly,all the symptoms that you are having are on left side of the lower limbs only.Other possibilities can be fibromyalgia, polymyositis (means 'many muscle inflammation') and polymyalgia rheumatica(an inflammatory disorder that causes widespread muscle aching and stiffness, primarily in your neck, shoulders, upper arms, thighs and hips. It literally appears overnight, but the cause may be a problem with the immune system, perhaps involving both genetic and environmental factors).
Pls discuss these possibilities with your doctor and get your blood sugar evaluated.
Hope it helps. Take care and regards.