Kinda Frustrated

Lost

So I came out to my mom about a month ago as bisexual and as happy as I am that she didn't decide to disown me or kick me out I'm frustrated that when I told her she said she knew I liked girls but that I'm just confused and it's just my teen hormones acting up. And it's frustrating because she's actually brought it up in an argument we once had about something completely different as if I was somehow messed up for liking both male and females.