A few days ago my boil on my stomach came to head it burst and blood & pus came out, and I noticed just a small string. The Boil looks better and the redness is gone it's pink now. But the skin around the boil is still firm smaller then it was. Is this normal? How do I know if the core is out I have never have seen one? I am keeping neosporin and drawing salve on it. Any advice much appreciated!