Someone takes a photo and posts it online. They didn't photoshop something crazy into it, they didn't add any text, they didn't juxtapose it with another image to make a point. It's not a gif or screenshot or a piece of stock photography. It's just a photo they took.
That photo is not a "meme." Even if it's clever. Even if it's funny. It's their work.
Don't fuckin' repost it without credit. Don't pretend like you took it.
If you have a fediverse account, you can quote this note from your own instance. Search https://beige.party/users/maxleibman/statuses/115738063934932800 on your instance and quote it. (Note that quoting is not supported in Mastodon.)