Hi there i had the same issue as well and appears alot of people have the same problem. The shiney leaves, dark color, and copper spots are nitrogen toxicity.
It happened to me just as flowering started and she didnt need as much nitrogen. All u can do is layoff the nitrogen and give it more PK which is what it needs at this point.
The leave wont go back to normal but any dried out leaves i removed. https://www.growweedeasy.com. go to that site great source of info