This is what I think happened that I wrote on another comment:
It's weird, but I had Fedora installed on my secondary SSD. Apparently when I did a clean Windows install, it installed in the primary SSD but took a part of Fedora on the secondary SSD as a Windows EFI partition. Then, when I installed EOS I selected "erase the disk" for the secondary SSD. I think it erased that EFI partition and I couldn't go back to windows, but since the primary SSD still had my files I could still see them. To be honest, something like that never happened before so I'm not even sure of what I'm saying.
Tbh I'm not even sure if that's what happened, I just didn't find an easy solution apart from starting over.