I can't see where your hair starts or ends.
It all looks 100% natural, all round.
The density is perfect.
You have TOTALLY pulled this off and done a brilliant job.

Unfortunately when you dye a piece, because the hair has been highly processed, it absorbs the dye very quickly, unlike your natural hair would.
10 minutes is about the max you can leave it on the hair.

But hey, you made it work out in the end.
I hope your pleased. You should be.