I had 2 camellias planted about a month ago. About 10 days ago, I noticed two stems had very droopy leaves, but green. Water did not correct the problem. It was extending down the stem. After several days I noticed what seemed to be Aphids(black) on those stems. I sprayed the plant with Orthene. The damage seems to have stopped, the leaves on those branch are falling off(green),and no new growth starting. The effected branches scratch green.

Should I cut the branch off or leave it alone? should I re-spray? If so, when?