I'm A 38 Yr Old Male, For Some Time Now

I'm a 38 yr old male, for some time now maybe once twice a month or less I've experienced a needle like stabbing sensation or like a cactus thorn was in my nipple and I brushed up against it. But recently in last week I've noticed a little more pain and discomfort along with a lump or swelling under left nipple. Any thoughts??? Never mind I didn't know the question would cost $20