This is in the wrong forum, but, I think you have a Mimiyoritchi. It does look like it has pigtails, but that's just the way it looks. It could be a boy or a girl. I have Hidatchi, and that one looks sort of like a girl, too. .
It is not possible to get twins on any Tamagotchi except for the Tamagotchi Angelgotchi. Sorry. .
Well. First of all, tamas look very different and It dosnt matter if its a boy or a girl tama. And for the twin thing I personally think Its just a rumor in the first place. I realy dont think you can possibly have twins on a tamagotchi. BUT.....Dont get me wrong....I might be wrong and you could have twins but I think you cant.