A lot of my wall space was originally painted with a pale jade color (flat) paint. I kept the leftover paint in tact in my attic. There were many small places that needed a touch-up and since I had plenty of paint left, I decided to do a spot touch-up (see photos) to avoid having to repaint a large area of wall space.

Same color, same texture, and I thought when it dried it would look more like the original paint, but it looks awful. Should I have used primer first and the paint? Or would that made any difference.

I don't want to repaint so many large walls that have various spots of paint on them; is it imperative that I have to, or is there another simpler solution? Please advise. Thank you.