What Causes Pain & Cramps In The Calf Muscles?

I had a distectomy and decompression operation late in november on L4 and L5 and post op was told I had a blood clot which would dissolve itself. Two weeks after the operation I started with a cough and 6 week later I am still suffering especially during the night. In addition I have had pain and cramps in both calf muscles. I have seen a nurse a few times and after an initial chest infection and short course of antibiotics have been given an inhaler which gives me no relief. I am unsure if this is related to my operation or just a seasonal bug can you please advise.