The good thing about making a mistake is that you have the chance to try something new. I took the sewing table apart and made new sides. Now it will be the correct height.
For the finish, I tried using Plaid maple stain right out of the bottle. As you can see, that didn't work.
Then I tried rubbing neutral shoe polish on the wood to seal it. Here you can see the pieces of the table with the shoe polish and one light coat of stain. Much better.
Now I'm gluing the table back together again.
I'm happy with how it looks so far. I think Grandma will appreciate that it will be the right height too. I wouldn't want her to get a sore back from leaning over a table that was too short. :D
Hope you have a nice day!