My roommate “accidentally” locked me out overnight

Hi everyone, I could use some advice. I (F24) live in an apartment together with my roommate (F23). My roommate has a quite different daily routine than mine and usually goes to bed around 10PM, while I usually have plans in the evening and get home later. Yesterday I was home for dinner with my roommate and we talked about our weekend plans. I told her about my plans to go out that night with friends coming from out of town.

Later that night when I came home I couldn’t get in because she had double locked the apartment. We have one normal door lock with a key that opens from both sides and one lock with a chain that only opens from the inside. I tried calling her about 600 times, rang the doorbell relentlessly and even climbed to the first floor balcony to knock on her window. She had her phone on ‘do not disturb’ and I couldn’t get her to wake up until 9AM this morning.

I just got home and although I am usually quite an easy-going and chill person, I am feeling extremely angry with her. I am a 24-year old women and her recklessness caused me to spent the night outside. I haven’t spoken to her yet, because I don’t want to say anything that I might later regret. She has sent me a text saying “sorry, thought you were home”. My question is what I should say to her and how angry I can be?

Next to that, I am also angry because I told her I would be home around midnight and would not make it too late as I had been ill earlier this week and have to catch up at work on saturday (today) and sunday.

Hopefully you guys have some advice. Going to get some sleep now.

Edit: I got some sleep, still feeling mad, roommate still hasn’t really apologised besides the stupid text, took off the lock, thinking about not renewing her lease since I’m the primary tenant. Thanks for all the advice, helped me a lot!

Edit 2: Talked a little to my room mate today. She half-laughing asked me what I had been up to the whole night. Told her immediately to save her words because it was really unacceptable. She still did not apologise until I asked for it just now. Still really mad though. I get that it can accidentally happen (don’t want to assume malintention), but the way she has dealt with it afterwards is really bothering me. I told her she should take accountability like an adult and that I did not feel she was taken the severity of the situation seriously.