main gauche dagger ??

[francantolin]

Hello everybody,
I just bought this dagger in an auction,
I wonder if it's an old one ( 17th ? ) or copy.
Length 17,5 inches
the blade seems antique and has engravings fulled with brass ?
the guard is interesting with the snake? heads.
Hand protection with a fleur de Lys ?
the pommel has the shape of Carlos V sword ( a lot of copy !...)
and five dots .

Perhaps too fancy and heteroclite for be true...