However, the Gunners youngster, who turns 21 later this month, produced the perfect response on the pitch which was capped with a fine goal in the 3-1 win.
"I have had so many injuries this season, people don't realise how hard it is to come back from setbacks after setbacks after setbacks," said the former Southampton trainee.
"You can't be at your best straight away and if you think you can, then you put more pressure on yourself. That's what I had been doing this season."
Walcott continued: "I heard what has been going on and what he [Waddle] said, but I don't listen to people on the outside of football.
"I listen to people around me - the boss [Arsene Wenger], Mr Capello, my family and the people around me.
"I have got fantastic people who look after me. I am very level headed and keep my feet on the ground.
"The best thing is I do know what's going on on the outside, but I don't listen to it, I only listen to people around me.
"It's doesn't bother me whatsoever - maybe if I keep performing like that it will shut people up."
Walcott, though, is not about to rest on his laurels.
He added: "Hopefully this is a kickstart for me, but I am not going to get carried away or too big about myself.
"I will look back at my performance and see what I can do better.
"I will study my performance on a DVD and see what I can do better, and will take whatever I can into Tuesday's [Champions League] game against Porto."
Walcott confronted Burnley defender Daniel Fox after a sliding challenge during the first half, with memories of Aaron Ramsey's broken leg last weekend at Stoke still fresh in the Arsenal players' minds.
The Arsenal forward, though, revealed there were no lasting ill feeling.
"At times it is difficult to focus after seeing Aaron injured like that," he said.
"In the game, there was a challenge on me and I probably overreacted.
"That was because of past events. In the heat of the moment, I just showed my emotions.
"We have had a lot of injuries this season, myself included, and we want to do it for all the injured players - especially Aaron."
Walcott, who joined Arsenal in a big-money move when still only 16 during January 2006, found himself thrust into the spotlight when he was a controversial inclusion in Sven-Goran Eriksson's World Cup squad despite not having featured for the Gunners first team.
The young forward feels he has come a long way in a short space of time.
"My development has gone very well. I am only 20 still and I have been in the limelight all the time," he said.
"As a young player, you normally do your development in the background and build yourself up, but the World Cup 2006 call-up shot the pressure on me straight away.
"I dealt with that quite well, but hopefully I can just get all these injuries out the way and concentrate on a very important run-in."
Walcott added: "The thing is I am always the country's biggest hope or the country's biggest disappointment.
"You set standards for yourself and you want to be as good as you can every single game, but sometimes it doesn't go your way.
"Now, I have had experience, I played in the Under-21s and played in the Premier League.
"There is definitely more to come from me, but those experiences will now move me on to great things."
Arsenal moved level on points with Chelsea, who have now played a match more, following what was a fourth straight league victory.
Manchester United are two points clear after they won at Wolves, but Walcott knows there is a lot of football left in the title race.
"Of course we believed we could get back into the title race and we have shown that lately," he said.
"It is a funny season, everyone is beating each other - but we have shown that belief and hopefully that will remain for the whole season now."
Arsenal 8/13, Draw 13/5, Porto 4/1