Forgive me, I didn't read all of the previous posts so I may be repeating info.
My friend had a lump much like you describe with the pain, but it wasn't a clogged milk duct. It was a painful cyst type lump and her midwife said to cut out caffiene for a week. By the end of the week the lump was pretty much gone as was the pain. Odd, but the truth.
I said a prayer for you, and I am sure it will be heard!
peace and love,