Why Am I Having Tremors In My Hands?

hello , i am 26 year old , i have been suffering from tremor in my right hand and my left hand norms , my tremor usually occur when i want to write using a pen , it does not disturb my other activities apart from cramps after any tedious work with my hands , i have taken some medications for Parkinson disease but non has relieve the tremor so i don't really know what is wrong with me .
i need possible remedies , Please