An already difficult campaign hit a new low as abysmal defending yet again proved costly, handing the Baggies just their second win of the campaign and first under Sam Allardyce.
Wolves are 14th in the Premier League and in danger of being pulled into a scrap towards the bottom if results do not improve quickly.
When asked for a message to the fans in the wake of the loss, Nuno said: "We are disappointed we didn't achieve what we wanted to give them, a good game, good performance and good result which can make them happy in these tough moments.
"We are disappointed. We are disappointed with the way the game went. We reacted well but we started very badly in the second half, and after that, everything was very difficult for us."
The Baggies – without several key players including keeper Sam Johnstone who has Covid-19 – took an early lead as Matheus Pereira scored a penalty after Willy Boly tripped Callum Robinson.
Fabio Silva and Boly then scored to give the hosts the lead at the break, but Albion turned it around shortly into the second half through Semi Ajayi and another Pereira spot-kick.
Wolves are now 12 without a clean sheet in the league, having also conceded first in nine games in a row.
Nuno added: "There is only one solution, go to the training ground and work and analyse, and find better solutions for the team.
"We didn't defend well as a team. We tried to change and find solutions on the bench, and we had chances but didn't achieve it."