Best friend’s crush?

Me and my best friend both had a crush on these two high school seniors last year and we never really did anything, since they were just crushes of course. But she did talk to her crush a couple of times and they both kind of knew each other. After they left i completely forgot about my crush and it wasn’t until a few weeks ago i encountered him at a party and we talked a little but nothing big. She told me a few months ago she was completely over her crush so yesterday night when I was at a friends house and he arrived I didn’t really say anything or think of him as my best friends (not to be possessive, just girl code). We actually had a LOT of chemistry together and we kissed twice half-jokingly. Today I told her about it and she did tell me it kind of bugged her, and I do think it’s completely fine. This may sound stupid to many people but I really am confused, am I a complete bitch if I go after him? What if we get along so well? My best friend is always more important but shouldn’t she be okay with it if she sees we are great together? ok this is stupid. thanks if you read though!