Did i mess up, and what should I do?

So, my only bisexual friend i have (that i know of) asked me if i was straight the other day. For clarification we are both girls. Idk if she needed to talk to someone about something or if she likes me or smth, but yeah. So i am bisexual, but I haven't came out yet, no one knows except my online reddit friends. So, i panicked and said yes. She seemed dissapointed, and i was like oh crap now she thinks im straight!

I'm soo scared to come out. I know all of my friends would accept me, one of my friends came out to me as lesbian, and then obviously this girl came out as bi, and everyone accepts both of them. It's my parents I'm scared of. Well maybe not? They are pretty homophobic, but said before that they dont care if i like boys or girls, my dad even asked me before if i liked girls (i obvioulsy said no). But then, ok, they know, but then they probably gonna put it in facebook or smth and now my grandparents and great grandma know, along with countless other ppl, like my teachers and stuff.

I know this post was probably way too long, but i needed to vent.