Johnson said: "After a disappointing result and performance in the final that was exactly what was needed.
"We wanted to start where we left off in the final and we did that. The lads started well, kept the pressure on and did really well for the full 90 minutes. There was only one team in it.
"We all wanted to give the fans a performance in the last home game. It wouldn't have been nice to lose the last one. It's great to finish at home with a win and score a few goals.
"Now we have to try to get another three points at Swansea and try to finish as high as possible. We want to finish seventh and if we beat Swansea we've got a chance of doing that."