What can cause dystonia? my hands are mostly affected with it. it's slowly occurring more frequently, atleast twice a week now. should i be concerned?

Many possbilities: There are many possible causes of dystonia. Some are genetic, some are "secondary, " which means they are caused by something else, including possibly a side effect of other medications. You should see a neurologist, possibly a movement disorder specialist, to see if the movements you're having are actually dystonia and to discuss causes and treatments.