All the labels are made up, there are no rules, and you might identify with multiple categories. I use the labels bisexual, pansexual, and lesbian interchangeably, because they have different connotations and familiarity to most people. Need to communicate that I'm with a woman? A lesbian relationship. Want to make it clear that I'm attracted to all sorts of gender identities? Bisexual/pansexual, depending on who I'm talking to and what terms their familiar with/how specific I feel like being.

The labels don't have hard and fast rules. I'm attracted to women, I'm gay, I'm lesbian, I'm non-binary, etc. It doesn't matter. They all apply to me and can overlap to varying degrees. I know a trans guy that calls himself both a gay man and a lesbian. I know trans women that refer to themselves as twinks. Specificity and semantics aren't as important as communicating what you intend to whoever you're talking to.

Gender and sexuality aren't hardwired rules, but influenced by our culture and environment. This is true for everyone. This isn't to say that someone's gender or sexuality isn't intrinsic to that person, but how they think about those and present them are part of an ongoing performance for themselves and others. If you're interested in learning more on the subject, I can recommend some excellent books on the subject, or feel free to ask followup questions here or in DMs.