He may be a superstar for his fans and critics alike but as per actor Shah Rukh Khan, there are moments in his life when he feels like a "loser", something that only pushes him to work harder.

"I feel like a loser over everything. I was with Aamir Khan the other day. And he asked me 'Why are you like this, Shah? Why do you think this way?' I got to know after talking that he was also thinking the same way. He wasn't asking me out of surprise, he wanted to know the answers for himself," Shah Rukh said on Friday at the trailer launch of his upcoming film Zero.

The 53-year-old superstar believes it is "always important to have lack of over confidence".

"Over confidence is worse than feeling like a loser. I feel I work harder when I think I am not good enough. I always feel I'm not good enough. I sometimes joke that I don't know how to dance, I've five expressions but I genuinely believe them, that I'm not good at everything, so I've to work harder," he said.

Shah Rukh plays the role of a vertically-challenged person in Aanand L Rai's film, which is set to be released on December 21.

He said when he was shooting for the film there were moments of doubts which he believes every creative person experiences.

"All of us had moments where we used to wonder if this is right, should we do this or not? There are so many issues actors and stars have, me the most. I'm insecure at times, overconfident at times, happy and extremely sad at times.

"I'm happy with what I've done and I am happier and even sadder what I shouldn't have done and what has gone out of my hands, what is coming to my hands and all these things come together and make you feel loved when you do the right film."

When asked how he deals with stress in his life, Shah Rukh said stress and anxiety will always be there at every stage in one's life.

"There will be stress in life. I am 53 today and half my life is over, I am in a profession where every Friday life changes. Some of my films have done well, some have tanked. Some things have went well, some haven't. It does feel bad. Maybe out of 70 films of mine only 30 have worked. It is not that there is success rate. But at the end, everything goes well," he said.

The Jab Harry Met Sejal actor said he usually spends his birthday meeting friends and fans.

"One should not own anything. I don't own my birthday also. I don't get to be with family much. I usually have bath, meet friends, media and fans. It feels good that everyone loves me so much.