You have to figure a way for a second touch function to not be acted upon by your events. Remember, the events run every tick, so the only way to ignore a touch event is to add a condition to the touch trigger so that your code can identify when the trigger has been actioned before. You can't simply disable touch on an object, it doesn't work like that. There really are a lot of ways you could do this.
One simple way is to add an object boolean to your sprite - something like object.Touched. Check that the boolean is false during your touch trigger and then set it to true during the subsequent commands so that the touch event trigger cannot fire again.
Also remember that if you have mouse input set to yes on the touch object then that can also trigger two touch events on some iOS and Android devices.