Raul Jimenez handed Fulham an early lead before Villa took control. Andreas Pereira also had a penalty saved by Villa goalkeeper Emi Martinez.
Tete later said, "Obviously a disappointed feeling. I think we started well. Then we were unlucky with the own goal. But, we get a penalty and we didn't score it. It is going to be a difficult afternoon.
On the penalty miss, he also said: "It happened and you have to push for more - it is what it is. Half-time we changed the game-plan, it was a bit better. Then it goes 2-1 and you know it is going to be difficult.
"We could have had a bit more luck, but I don't want to point to that. It wasn't our day and we could have done better.
"We can look in the mirror and we have to do better and train harder. Frustrated."