From the error dialog it is clear that something around your connection is wrong.
First be sure that everything you included here matches: you have an error about localhost and port 3082 and you present a connection dialog with a foreign host and port 5432.
Then you have to teach PostgreSQL that it should accept connections from your home. This can be done via the
pg_hba.conf file. You will need a line added like this (the header is already there) - if you don't have access to it, ask the person in charge of it to do this:
# TYPE DATABASE USER ADDRESS METHOD
host dnizetic dnizetic 18.104.22.168/32 md5