So... I have issues with this series.
Sayaka's reactions. They make...almost zero sense.
First, remember she doesn't actually remember anything at all. She is just going based on her notes her past lives wrote. So at the beginning of this chapter, she talks about the despair of being alone and having tried to ask an adult for help, and the reader is supposed to...sympathize with her? How? She could only "feel" the despair written from the notes of her past self. I guess she could be honestly sympathizing with her past self, but it seems weird. This is honestly a minor issue.
But that leads to a larger issue. Like...what are we, as readers, supposed to feel with that last scene? Akane "lost" her memories? We know she just regains her memories at some random point during her run. Could be the beginning. Could be the end. Sayaka, in the past life, even mentioned that she just gains the memories at some point. So it's understandable Sayaka is concerned Akane doesn't remember, but...why should the reader care? I'm left thinking is this supposed to be a cliff hanger? We literally already know this is something that could happen.
And lastly, why is Sayaka going to Akane so early on? In all the previous lives, she didn't, I don't believe. So, it must be something she read in her notes from her past lives. But...what? She had all of zero time to write anything about the school clinic. The only thing she could've written was that they were looking for Izumi for a week. Why would that make Sayaka want to rush to Akane?
Honestly, the author might be able to explain these things. It's possible. But the more likely answer, to me, is just that the author wanted to do this cliff hanger, drama, suspense thing that...makes zero sense the more you think about it.