Hard lump on forehead after lipoma removal?

I had a lipoma removed from my forehead 2 weeks ago, after the initial swelling went down after the first few days I was left with a hard lump that is in the area that was operated on. The lipoma was definitely removed and after the surgery was complete I felt the area and it was flat and smooth except for the stitches of course... I've read many things online as to what to do and what not to do to speed up healing process but there are alot of contradictions... can anyone help and advise???