Interesting, interesting ...

All right, I'd consider you a native speaker of English since you spoke it at home regularly and you don't even have the option of government information in anything but English, but you have to remember that English is an official language of Hong Kong too, so you'll have to prove to people that despite similar situations, you have native speaker status and they don't

Oh, and if anyone asks you where you're from, you can say "Well, I'm ethnically Filipino ..." and just leave off. Everyone will assume you're from the States or whatnot, depending on your accent. It's not like you're lying or anything :P