Due to some really f---ed up people below, the problem is that the "25565" port is already in use. You can get around this by making sure it isn't, or heading into your server.properties file and changing the port to something like 25566.
You mean yesterday? Its the 15th.. also, don't use Server.pro. Pay for a host. If you have no money, don't even try to run a server. And what kind of staff? (I should ask I guess haha)