Slowrolling is not nice.
What site are you playing on and do you track your play?
Against a full table of random hands, AA will win under 30% of the time.
Against any individual random hand, AA will win 85% of the time.
Presumably, your tournament featured full tables. That means that if you play the hand in a way that keeps too many opponents in the hand, you are going to lose very frequently. In the long run, it will be slightly less often than you experienced, but not by much.
This is part of the reasoning behind the advice to play AA aggressively in order to narrow the field.