My first problem was the brush. While I thought it was quite a small brush, it was actually a little larger than it should have been, and I had a little trouble covering the flower without going too much out of the lines.
My second problem was the background. I decided to use my distress ink markers, scribbling them on an acrylic block, spritzing with water, smearing a little together with my finger, smooshing the block onto my paper. There was a little too much water on the block, I think, and when I lifted it to smoosh, it ran all over and didn't look as good as I had imagined it. I blotted the paper with a paper towel, then tried again, this time using fewer colors and a lot less water. This seemed to work better, and actually gave a little depth to the background.
I rubbed off the rubber cement when it was dry, and discovered I hadn't covered the stamping as well as I had thought, and there were little spots where the watercolor had gone through.
Overall, I think the project came out pretty well, and once again I have discovered several things I should not do the next time I attempt this, as well as a couple of things that I liked.