Hi welcome to HCM.... You are having calf pain with walking few distance .... So vascular thrombosis should be ruled out. ... Here your detail history with smoking habit and drug history taken along with physical examination..... The causes can be many like ..... -peripheral vascular disease -neuropathy -diabetic neuropathy -myopathy -electrolyte disturbance etc .... According to examination investigation needed with that of colour dopplet , neurological examination , nerve conduction study etc..... Than According to cause treatment given . Like for b12 deficiency neuropathy b12 injection given... For thrombotic vascular disease low molecular weight heparin needed Take care Advise : Physician consultation for examination....