I've had a lump behind my nipple for quite some time and although I can see it on the mammogram, it has always come back clear. Lately though it has grown and it sore and hard. I have an apt tomorrow but in the last few weeks I have been so anxious and worried. Does anyone else have a cyst that has grown and is sore? My periods are all over the place too, but that coincides with my age (49) but also taking pregablin. Any experiences would be appreciated.