I Am Experiencing Pain In The 'v' Shape Of My

I am experiencing pain in the 'v' shape of my hand between thumb and index finger. Inside of a burn throbbing almost like sore muscles but not. Started about four days ago. Hurts to write notes and when I put pressure on it. Sometimes the pain spreads to my knuckle and up to the bend of my finger. Sometimes I feel no pain at all but when I do, it really hurts. Should I be concerned?