I have a mole on my left nipple that has upset me for years. Help?

I am not familiar with ACV, but it does not sound like it is working well for you if you are sore and swollen.  The best advice I can give you is to see a plastic surgeon who determine the best option for removal of this mole.  Performing non sterile procedures on yourself is not a good idea because you can get an infection around your nipple which could potentially cause a much bigger problem.  Best of luck!