The Canaries followed up the midweek win over Cardiff by beating Plymouth at Carrow Road on Saturday to climb out of the bottom three with seven games remaining.
Gunn said: "We know there is still a massive job to do with seven games to go and we have to focus on the next one. We've given ourselves a chance.
"We know it's going to be a massive game against Birmingham next Saturday at St Andrew's but it's one now that we go into with a lot more confidence and a lot more points than we started with at the beginning of this week.
"The players are believing in themselves now. There was a blip which we'll not mention but they have recovered well from that and they have shown a lot of character.
"To go out there in front of 25,000 and grind out that result will give them all confidence."