Will this hard internal lump on my forehead disappear after lipoma removal surgery?

I would discuss with your surgeon. You may have a seroma or hematoma that is causing the swelling. Best, Dr. KaramanoukianLos Angeles

Thank you for sharing your question and photograph and I am sorry that your results have not been what you anticipated.  I would definitely see your surgeon for an in-person evaluation.  You have most likely developed a fluid collection in the form of a hematoma or seroma that should be aspirated.  This will hopefully allow for sealing of your skin back down to the underlying tissues preventing reaccumulation.  Hope this helps.