I Am A 78 Year Old Male In Good Condition

I am a 78 year old male in good condition for My age, but my right small little toe has begun to be very painful. I first noticed two weeks ago playing golf, I RIDE A CART SO THE WALKING IS MINIMAL. I ALS EXERCISE on a fairly regular basis. The toe smarts/hurts when I play golf. Toe has a small blister between little toe and the second digit. What is wrong? It has not been banged or in someway damaged, no reason for soreness. ???
Dan