Did you actively visualise a form for him to inhabit, as my tutorial suggests? 
If so, you need to watch that for any movements, any changes to the eyes, especially, or any words or images that appear in your mind.
Take note of them without trying to criticise or evaluate them, later you can apply common sense to interpret things.
And 17 isn’t a child in the way that tut means, it means a child who is not interested in doing magick, and whose defences may not yet be strong enough to have evocations going on right in the same house.
One can perform evocations safely even with sleeping sick kids and so on, but I wasn’t going to try and delve into that in a begeinner tutorial I also intended to be simple to translate. 
If you’re having trouble with the visualisation part, take a look at the method I define in this walk-through I did with a member a few years ago.