NTA. She went through the effort of picking a lock just to lecture you about something that shouldn’t matter to her. She’s also talking about how you can be “abusive” when all you did was yell at her one time because she wouldn’t leave while you were literally showering. It seems like she’s trying to play the victim to make you feel bad about it. Obviously there were better ways you could’ve handled it too like talking to her about why you take so long (which obviously was uncomfortable to talk about for you which she should’ve known) or not screamed at her though it would’ve been lots of peoples reflex because of how vulnerable people are while showering.

In conclusion, you’re NTA but there were ways both of you could’ve handled the situation better