I'm must declare at the very beginning that I'm a PhD student that suffers from major impostor syndrome, and very much feel very unconfident about myself or my abilities.
That being said, I recently received a paper to review for a conference, and when I read the paper I felt it wasn't well-motivated, and the introduction was shaped badly. Even though I felt that the rest of the paper was okay, it was generally hard to follow for me. I'm someone with related experience in the field of the paper, I understood much of the paper after a thorough look, and evaluated based on my opinions. After a deep battle with myself, I decided to 'weak reject' the paper and sent in my reasons to do so.
However, the other submitted reviews were quite positive, and now I feel like maybe I didn't do justice to the authors' work by rejecting it. As I looked further into the draft, I saw some basic things that I didn't consider before. So maybe I didn't understand it well enough because I'm just stupid, and not because the work was actually bad. Now I feel extremely guilty and feel like I'm not capable of sending confident reviews anymore.
Perhaps this is a question for my therapist rather than you all, but being experienced in academia, I want to know if these feelings are normal, how to cope with them, and is it okay to reject a paper the way I did?