Welcome! well, she, or he looks pretty young..the easiest way to tell at that age is the voice. If she quacks loud it's a girl..if it's a soft, hoarse quack..kind of whispery..it's a boy
You could also do a vent check as well. If it is a male you will see his pickle which would be corkscrew shaped...lol and obviously the female will not have this. Do I hear an ewwww. Of course as shicks0211 suggested. Less intimidating... Steve