He told Arsenal TV: "It will never go out of my system, but we want to focus forwards and what is in front of us.
"Now is a good opportunity for us to show mental strength and to finish as well as we can, as high as we can because second place is still possible.
"Overall, I believe we have made big progress this season. We were very close to the two trophies which really matter to us and we want to go into the next season feeling we have moved forward."
He added: "I believe we will benefit from all which we have learned this year and will come back even stronger."