It's ok to vent. The most important thing is that you engage with her and continue offering your guidance without dictating her hobbies. I'm not certain the athletics are a priority at this point. She seems a bit down about not getting into those teams. She may be gathering her energy and courage to try something new (or not and that's ok too). Not everyone is as instantly reactive or able to bounce back immediately or on an expected cue. Some kids/people take more time to absorb and figure things out, chat with their friends and situate themselves more fully before feeling confident to try again.

She's probably also developing her own opinions of herself and, yes, those hormones are very likely playing a big role. Hang in there with her and continue being a loving and involved parent and show your interest in what she likes or doesn't like. I'm also feeling a lot of pressure coming from you. Wiseman pointed out some things in your post that might be having an effect on your relationship with her. Is she in a private school, by any chance? You may also be comparing her to what you might have done in your school years and feeling like she's falling short of what you have done in your youth or what you may have wanted to do.