Here is a free youtube video Suzanne Dean did on coloring with reds that may help you choose good reds and how to blend with them. They are the most difficult of the copics, actually so it is not you.
Copic Tutorial on Coloring with Reds - YouTube
And here, darling, is Sharon Harnist's step by step (with pictures) tutorial on coloring red roses... enjoy!
Guest Tutorial: Coloring and Shading Flowers by Sharon Harnist | COPICMARKER.COM
Post your image when you color new roses - I bet this helps you.
My Eclectic Spirit