Spurs could not hold onto Dele Alli's 49th-minute opener in Sunday's game, with Chris Wood's injury-time strike.
Spurs could not hold onto Dele Alli's 49th-minute opener in Sunday's game, with Chris Wood's injury-time strike earning visitors Burnley a 1-1 Premier League draw.
Tottenham have won just twice at the national stadium in 12 attempts since 2007 and have not claimed victory there so far this season while White Hart Lane is being redeveloped.
Yet Pochettino says their new surroundings have played no part in their poor start, saying: "I agree we can't have moments like this if we want to challenge for the title."
"We need to work hard to try to be more strong, because that is a mental problem that we need to fix."
"It's true that the results are too early to try to analyse what will happen in the future, because last season after three or four games you would never have said that Chelsea would be champions."
"That is why in football you have to try to work hard to fix the problems and it is clear we need to improve and increase our mental levels and become more strong."
Spurs have lost eight of the last 11 games they have played at Wembley and were beaten 2-1 by Chelsea in their first match there this season, but Pochettino refuses to entertain talk of a jinx.
"It has nothing to do with Wembley. It's not a Wembley problem," said the Spurs manager.
"In football if you're not concentrated and focused, sometimes when you're tired maybe a little bit and you're not 100 percent, you concede or give the opponent the possibility to score.
"That is how it was today and how it was against Chelsea. That was the key.
"It is not frustrating, but disappointing. My feelings are bad now and for the players it is the same and for our fans. But that is football.
"Last season when everything was going well, we were so happy. Now we have to try to keep a good balance and try to keep positive. We can only be positive."
Harry Kane was one guilty party as he missed a catalogue of chances, meaning he is still waiting for his first goal of the season.
"I feel sorry for him because he had the opportunities to score and always a striker needs a bit of luck," said Pochettino.
"But I am sure that Harry will start to score as soon as possible. I have no doubt about it."
Pochettino believes Tottenham will add new signings before the transfer window shuts this week, having only brought in Davinson Sanchez, who made a late debut against Burnley, and back-up goalkeeper Paulo Gazzaniga so far.
"Am I confident? Yes, yes, yes," said the former Argentina centre-back.
"For sure we will add some players who will help us in the future. I am so optimistic. We hope to sign in the positions we need to strengthen."
This was an impressive performance from Burnley, who frustrated Tottenham for long periods on the back of their opening-day victory at Chelsea.
"I'm not really interested in the Wembley effect on Tottenham -- they are a top side with some fantastic individuals. We are more interested in getting on with the game," said their manager Sean Dyche.
"I want a team who can be effective in different ways -- sometimes tactical, sometimes by playing pockets of good football and sometimes with blood and guts.
"It's not easy to go to Chelsea and win, especially by scoring three goals, and coming here to win a point. My only gripe would be we played better at West Brom at home and we got nothing."