5th dnd – Is the fall of concentration on a spell considered "affecting a creature" for the purpose of the Blink spell?

While under the effects of wink and on the ethereal plane, can you give up a concentration spell to affect a creature in the material plane?

The description of wink says: "You can only affect and be affected by other creatures of the ethereal plane."

The rules on the state of concentration, "You can end the concentration at any time (no action required)"


While you are on the ethereal plane, a teammate is shot in the area of ​​your Nauseating Radiance fate, knocked out, and start his turn. If you finish your concentration before your turn, you will also remove the levels of a creature's depletion. Does this count as "affecting a creature" for the purpose of wink? How is this resolved by the rules?