I can't see your pictures.
I know from own experience, that it is _not_ possible to share pictures from Google Photos to embed them here in your postings, as done by other users. This feature was explicitly dropped with the change from Picasa to Photos (Picasa still shares the pictures, but it is no more possible to add new ones), see Photo help page.
You can only share an album in Google Photos and post a link here, but the users have to follow the link to view the pic on a Google page. Embedding allows a much better experience but you need another storage place for that.
Cheers,
Frank