Indeed, I just modified my profile to have 15 posts per page (instead of 50) and I can see and post on the 2nd page.
If I still reduce to 5 posts per page, I can see the 1st, 2nd and 4th, but not the 3rd, where my post #14 at 4:44pm is. So it seems that it is my edit at 5:06pm that is the cause of the problem. If an administrator could take a look?