I bought, among other plants from a local garden center, a fuschia bush,
and on the label it says Colin Dorrington.

When I bought it the flowers were a light pink color and it looked
healthy. I planted it in my garden border , and it gets plenty of sun.
That was about 4 weeks ago, and now the flowers have died off and the
said plant doesn't look too healthy now. I have watered it twice a week
and fed it once a week since I planted it.

What have I done wrong