My sister always makes a lunch box for me, but today she woke up late and couldn't make it, so I tried to make it. I added chicken tsukune that I made last Sunday, plus vegetables and rice balls. (assuming you made more than one rice ball to add to the dish)

My sister always makes a lunch box for me, but today she woke up late and couldn't make it, so I tried to make it. I add chicken tsukune that I made last Sunday, and vegetables and a rice ball.... Actually this may look like bad English if you concentrate only on classroom grammar and attempt only to teach one particular grammar topic.. If you are attempting to say, you wanted to make the same lunch box that your sister usually makes you specifically , but were adding the Chicken tsukune you made last Sunday plus some vegetables and rice balls or a rice ball.. Then it is good English although it could do with some tidying. (no reason why you shouldn't meaning it's always for you, how is the reader supposed to know that, they are not physic.)

My sister always makes me a lunch box, but today she woke up late and couldn't make it, so I tried to make it. I made it with chicken tsukune that I made last Sunday, vegetables and a rice ball.