Photo albums not showing when trying to upload a photo

Ok so i am trying to upload a photo onto an internet forum. All my photo's are showing in the photo app, and in albums i have set up like normal.

But when i go onto the forum, upload photo, only some of them are showing when i select "photos" as the area to choose a file from.

It seems to be the most recent photos that i have uploaded from my iPhone a couple of days ago that are not there, and the albums are not there when i click the drop down arrow to show them.

Does this make sense?? Can anyone help?

Thanks