I have heard good things about this at-home hair color and clients who use it have good coverage, so this is baffling. This product is designed to be an easy at home hair color. For whatever reason, your ends just grabbed the color deposits more.
I usually like to wait at least a week after a haircut to allow the ends to close well before applying a chemical. Am one of those stylists who does not like to do haircuts before for fear the fresh cut ends will soak up perms and color. It could be that your hair cut was too fresh.
Speaking of "fresh", the style is for two toned hair coloring. Perhaps you should give this look a chance out in public around your friends or co-workers? Am very happy that your fiance likes it. And the color with the red coming through sounds so pretty. Are you sure you want to change that?
This brand is something I cannot specifically advise you on. I do know that the only way you will be certain to achieve all over darker hair is to buy a darker color. Look first to see if there is a phone number Garnier Nutrisse has for you to call for advice.
And I'm afraid to tell you, the only way you can get rid of those darker ends is to have them cut off. I know you don't want to do that since you just got it cut.
So three choices:
1. Call Garnier Nutrisse. They are the experts with their product.
2. Go darker all over with darker color, staying away from ends until last
5-10 minutes.
3. Getting the ends snipped off. The color change will be better found
with close-up lighting or out in the natural sun. (the latter is my
preference for color)
Good luck! And let us know what you find out/ decide.
Oh and btw, any chance of a before and after shot ? I would imagine lots of us would love to see the 'new you' .