Small fluid filled bump on pointer finger ?

A few months ago I noticed that there were a little bigger than Needle head sized bumps on my hand right hand. My pointer finger then starts to become itchy. When I itch it I get a reddish bump on my pointer finger that looks like a blister. It goes away and comes back a lot. Yesterday I popped it with a sterilized needle and light pink fluid came out. What is this? Oh and it only happens on my right hand and the big bump only happens on the same spot of my pointer finger.