What Causes Tingling Feeling In Extremities And Tremors In Hands?

I have developed tingling in my extremities progressing about a month or so. I also have tremors in both hands and a constant dull headache behind my left eye and somewhat down my neck. Also a slight tingle in my left cheek. What should I check for? My brother has lesions in his brain and Parkinson s being tested in hospital now. Any connection? Thank you.