Thanks for your suggestions. Waiting seems like the best option. For now, I'm just planning to comment.
Subreddits: ArchitecturalRevival, Autumn, etc.
I'm getting the same warning on posts I've shared without problems before (for example, two weeks ago). I had 23 followers, now it shows 0. This might be the pre-ban phase.
That's odd. Check if your profile and follower count are set to off.
Try after 24 hours; I normally get mine back. Slowly share again in different subs.