The New York Times sent me to Yemen last year to photograph protests against the regime of President Ali Abdullah Saleh. No one was really covering the story – most foreign correspondents and photographers were in Tunisia, Egypt or Libya, reporting on the revolutions there.

This was taken on my second day, after hours of intensive shooting and bombing. Twelve people were killed and 30 wounded that day. Early in the morning, I went to what was dubbed Change Square, where protesters were congregating, and marched with them until snipers attacked us. We retreated to the square only to find tanks firing artillery shells. I ran into a nearby mosque that was being used as a makeshift hospital. That was when I found Fatima holding her wounded son, Zayed.

It was chaotic. Everyone was crying. But Fatima was completely calm as she waited for a doctor to see her 18-year-old boy. His leg was wounded and I assumed he had been shot, but he'd actually fallen, intoxicated by tear gas. After the picture was taken, he spent three days in a coma. When Fatima heard that protesters had been killed, she went straight to this mosque to see if Zayed was there. This is the moment she found her son alive.

Their pose and the way the light fell made it easy to see the shot. In a matter of seconds, I'd taken five frames. I knew it was a strong image, but I was overwhelmed by the reaction it got. I didn't know anything about them at all – none of these details – until much later, when the shot won this year's World Press Photo award and I was able to go back to Yemen to hear their story properly.

CV

Born: Santa Coloma de Gramanet, Barcelona, 1979.

Studied: Trained at El País and El Periódico de Catalunya

Influences: James Nachtwey and Stanley Greene for their photography and ethics.

High point: In 2004, I did a story about Moroccan immigrants that forced the Spanish government to apologise and change its policy.

Low point: When I was fired from Getty Images for focusing on social issues rather than things that could be sold easily.

Top tip: Open a bakery! You have to really want to be a photographer to make it.