Bruce told BBC Sport: "It feels like a loss. Unfortunately, we've made mistakes and got punished. We've scored two wonderful goals which would have graced any arena. Apart from the mistakes we made late on, we looked a very good team.
"Individual errors are something you can never determine what it is. Is it complacency? Tiredness? A mistake is a mistake and we've got punished."
Hull are ninth in the Premier League following their draw at St James' Park.