Ola Aina and Orel Mangala scored the goals in a 2-0 win at the City Ground, handing Villa their first Premier League loss in two months.
The Villains have been excellent at home so far this campaign, winning all five of their matches at Villa Park, scoring 20 goals and conceding just four.
However, they have been considerably worse on their travels, with just two wins and one draw away from home and, while Emery is not overreacting, he knows they must improve on the road.
‘We always take it as a challenge to play away because at home they [Nottingham Forest] feel strong. To come back in the match and get a result was very difficult,’ said the Spaniard.
‘We started the match very poor but we reacted well, we had chances and opportunities to score. In the second half we started really badly and at 2-0 it is difficult to come back.
‘The players fought until the last minute to try and score but we didn’t do it. Of course it is hard to lose but we have to accept it.
‘We have to understand every match for us is very important. We have to be strong to keep our defensive ability and to try to get the points by being together. We made two mistakes early in each half and it is difficult to come back.
‘We won 11 matches in a row at home and that is fantastic. Away it is a challenge. Today I learned again. We are calm and relaxed, we have to be stronger defensively away and try to work hard if we want to get to be one of the top seven teams in the Premier League.
‘I learn when we are winning, I learn when we draw and I learn when we are losing as well. Today is one year since I arrived here. We have progressed and done a lot of work and I am proud of the players, but I want more. To increase the level is the next challenge I have.’
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