My gf 22 F pleasured herself on a voice call while I 22 M didn’t know

Context
Throw away because i know she has reddit
Me 22 M her 22 F have been dating for about a year, tbh healthiest form of love I’ve gotten, she’s the women I wana marry, and she feels the same. We both live in different apartments, difficult to move in together because of work, so we’re postponing it, dates, hangouts, sleepovers, still going strong and I love her, but last night, we were calling and talking, I was talking about random stuff, “What if a marshmallow was the size of the empire state building” type of random stuff, my laptop was nearly closed on my desk as I was laying down, and I was talking, getting sleepy, and I kept hearing groans from her end, I asked her “whats wrong?” Silence followed by slowly trying to just keep a one-sided conversation going, untill she moaned really loud, like I thought she was having a major cramp, or something that needed medical and I sat up and was asking “what’s wrong?!” She paused and asked “did you read what I sent you?” I opened my laptop to see her sending increasingly sexual messages while I was busy talking to myself, and after I asked, “why didn’t you tell me” she said “I thought you read them” after some silence, I laid back down and was thinking about it, and then a few minutes passed and she kept going. She asked if I was “doing” anything, I felt uncomfortable and like I was part of something I didn’t ask for, I wasn’t doing anything, so I said I wasn’t, she kept going, was I ment to say something, join in? I don’t know how to feel, I tried to get in the mood, but I just couldn’t, should I have? I’m confused any advice?