I discovered a lump in my right breast. I never noticed it before. When the dog stepped on it it seemed to be a little tender. This is when I noticed it. It seems to be abit large. It measures 3" x 2" and is rather solid. I had a breast reduction about 27 years ago so I've always felt some lumps in my breast area but nothing this large. It doesn't seem to bother me. Also I didn't notice this one or the one on the back of my neck near the base of my skull until after I started taking some over the counter medication for pinworms. Could this cause the lumps and will they go away once the medication works it's way through the system?