Their defeat in Spain ended Scotland's hopes of a playoff spot.
Adam said: "It is hard to take, but we will evaluate everything that happened and sit down as a group of players and see where we can improve and that's the way forward if we want to become a better team.
"You've seen last night that we can pass, move and create chances.
"We now have a squad who is close together and we are looking forward to the future.
"There will be plenty of friendlies before the next qualification campaign begins so the players will go back to their clubs and try to play as well as they can and try to get back in the Scotland squad for the next match."