I do not think you can fail at FIMming as FIMming is considered a fail with topping.
May be just wait a bit longer(1-2 days). I remember that I had something like yours in my current grow and it looked like I screwed up with topping but then in a couple of days two new tops started growing.
Also feel free to top as many times as you are pleased. I have done topping 3 times on 5 of my current grow plants and 2 times on one. Now I have from 6 to 8 main colas on each plant.