Dear zanybear, It is very difficult to say what you are now feeling, possibly there is a fluid build up that is being felt as the 2nd lump? It could also be that you are feeling an enlarged lymphnode, that has increased temporarily after the surgery. Or if they were only doing a fine needle biopsy and not removing the entire lump, the lump would still be in place. When you see your surgeon they will be able to answer you about what was actually done and hopefully reassure you that the correct area was evaluated.
Also, the lump(s) is not cyclical; it does not change size before during after monthly cycle. Pain does not decrease or increase before during after cycle.
It could be that the wrong area was biopsied; but it's also true that it's very common for the area biopsied to get quite lumpy for a while after surgery. I tell my patients it may feel like the lump wasn't removed for a while, for that reason. It needs followup when that happens.