What To Do For Numbness In Hands Causing Pain, Inability To Do Daily Activities After Shovelling Snow?

After shoveling 1-3 inches of snow (approximately) every other day (approximately) for the past week, both of my hands are going numb, tingling, swollen and are very painful when I grip things and try to make a fist. During the night I wake up because my hands are numb and very painful. It takes a while to get feeling back in my hands regardless of the fact that I have my arms straight at my side while standing up in order for the blood to flow to flow most efficiently to my hands. When I grip something, the pain radiates from my fingers to my forearms and hurts especially from the end of my hand/ palm to about an inch down my forearm on the underside where the veins run. Even while writing this on my mobile phone, my pinky, ring and middle fingers start to tingle and go numb. What could be wrong and how do I fix it as it is interfering in my every day activities?