ouch, ouch, ouch.
i also had this done some 16 months ago after a car accident and now have 2 plates and about 11+ screws and experience pain daily, some times worse than others. as i was overseas when i had the accident and surgery when i was cleared to fly home they gave me what is called a split cast in case of swelling and when my wrist is really bad i put this on and it helps. i also often strap it firmly underneath the cast. i have had extensive physio (which helped me regain quite a bit of movement) and numerous exercises to make sure it was healing correctly. in spite of all this i have lost some 50% of the movement and things i can do and it will never get any better from here on in.
don't mean to depress you any further but there is nothing further i can do so am now trying to cope with the pain. my doctor tells me that muscles, sinews, nerves etc all undergo great trauma and sort of have long memories.
you on the other hand have now depressed me as you are some 8+ years further on than me.
i am sorry the best i can say is get it checked out by your doctor and/or orthopaedic surgeon to make sure that there have been no changes and see if you can get some advice on pain management.
in the meantime take pain killers when you really have to but try and cope with it. relaxation and accepting the fact may help.
easier said than done. sadly pain can become really depressing so watch out for it.
sorry this is so long and possibly not much help except to say i can really relate to this. good luck and hang in there and know that you are not alone. at least we have the arm however useless it may be. mind you there have been times when i wished i didn't have it.