Spawner Problem (I'm not sure if this is a bug, but please tell me)

[Canada_MC]

What is the bug: So, I bought a creeper spawner last v, I have a base for it, today I was changing somethings with it (Trying to make it more efficient). I had put torches all around and over the spawner, thinking it would not spawn any creepers. I was about 3 to 5 mins into building when I hear an explosion, a creeper had spawned, and blown up my spawner (Which is what I am kinda upset about). The thing is that no creepers had spawned for about 3-5 mins with the torches on it, there was enough light in the area for a natural one not to spawn. I am posting this to make sure what happened is not a bug, and if it is can I have my spawner back.


Where is this bug located: Freeworld


How can we recreate it: Put torches around a spawner, wait for something to spawn, specifically a creeper spawner.

Thank you for taking the time to read this.