Is White Lump, Sore And Swollen Breast Around The Third Nipple Serious?

I have had a third nipple on my right breast since birth, it has always been like a little white lump, but 6mths ago it changed colour and became very sore and my whole breast has swollen. My GP has been treating me with antibiolics for 5 weeks and the pain is still there, there is cancer history in my family which worries me slightly, but I have no lumps in my breasts. I want to get it check at the hospital but GP will not refer me, I'm 36 and have had no children. What do I do, I'm in pain everyday ??