Trying to get the right paint sheen for my upstairs hallway - was painted 3 years ago, but the contractor apparently "mixed" his own paint color and failed to leave a sample.

SCORE: I mixed what is now spot on for paint color match!

FOUL: The sheen I mixed was satin, this way too shiny/glossy.

FOUL: I tried chalk paint, this way to too dull/flat.

QUERY: If I take my paint sample of color I made, would I be able to get paint mixed to match? What size sample do I need to take? - Lastly, would it be best to ask for "Eggshell", based on my two above failures?

THANK you so much !