It's not good news I'm afraid.  You've been hit by the RED Palm Weevil (as have many of us).
There are ways to help prevent it but I'm afraid that by the time you see the symptoms, it's too late.  I can provide more info if required.
If you have neighbors with palms, you need to get rid of your trees as quickly as possible and warn them of the problem so that they can hopefully take preventative measures before it's too late.