At first he thought it was some sort of sick prank. Then came the screams. And as his fellow music fans fell to the ground, Domenach's survival instinct kicked in.
"I got down and I said to myself, 'OK, the only thing you have to do is hide your head, and if you're injured you'll be injured on your arms or your legs and it will be OK, you will survive ... I put blood on my head and my arms ... [to make it look like] I am dead. Maybe it will work."
He was finally able to escape when the gunmen moved away to another part of the venue. Others were not so lucky; 89 people died at the Bataclan
, and another 41 were killed at sites across the city, as terrorists stalked the streets of Paris.
"Afterwards, one of the special forces [personnel] came up and said 'You were really brave, what I saw in the Bataclan was the most awful thing in my life, so I am glad to see there are survivors. Please, now get on with your life.'"
Four months on, Domenach was doing his best to follow the officer's advice. Then, a week ago, as he scanned his Twitter feed before heading to work, word of the attacks in Brussels started filtering through.
"[People were] saying that there was this explosion in Belgium and instantly I understood what happened, that it was another attack. I knew right away," he recalls.
In tears, he begged his girlfriend not to take the subway to work, then spent hours glued to social media and the TV, desperate to find out what was going on.
"It was just awful. I felt like it was the second November 13 for me," he says.
Samia Maktouf, a lawyer for many of the families of those affected by the November attacks, says the capture of Paris suspect Salah Abdeslam and the ensuing carnage in Brussels has left them suffering renewed anxiety.
All have been forced to relive the trauma, and while some want to cut themselves off completely from what has been happening in Belgium, others find it impossible to tear themselves away from the news.
"It hurts them a lot," Maktouf explains. "They feel as if they are living again and again the French attack."
Guillaume Denoix de St Marc, who runs France's Association for the Victims of Terrorism
, says demand for the group's services has spiked in the past week.
"Just after the attacks in Brussels, we had many phone calls and contacts with the victims of November in Paris because it reopened all of the wounds that they had."
Denoix de St Marc's group is doing what it can to support the survivors and relatives of those killed in Belgium, and hopes to foster links between Paris and Brussels.
"Maybe in the future they are going to meet together," he explains. "That's what we're trying to do because it's important for all victims to meet other victims of a similar tragedy."
It helps, he says, "to see that, 'The others are moving on so it's possible for me.' ... We have to go forward because we don't have the choice."
Aline Le Bail-Kremer from the Association for the Victims of Terrorism
, lost her cousin in the attacks.
She has been helping to support a French survivor of the Brussels attacks. "The principal point we discussed is 'Can I be better one day?' Yes! Maybe it will take some time, but it will be better.
"It will be a very different life than before, a lot of things will change, but everything will be better."
The most important thing, Le Bail-Kremer says, is for the survivors and the relatives of those who died to know that "they are not alone."
Solidarity and hope
Domenach, like many other Paris survivors
, feels huge solidarity with the people of Brussels, and particularly with those who have lived through the attacks, or lost loved ones.
The path ahead will not be easy, they warn, but it is possible to make it through. "It will be really hard," says Domenach, admitting: "It's hard every day.
"Their life will be changed forever but they have to continue to live, to fight, to show that we can recover. We can come back stronger and show the terrorists that we are not weak.
"Even if we don't have weapons, even if we don't have bombs, we are citizens, we are democrats and we are better than them."
Denoix de St Marc speaks from experience: He lost his own father to terrorism, in the bombing of UTA Flight 772 over the Sahara in September 1989.
He says that with help it is possible to move on, eventually.
"You don't think there is a future for you, your 'timecode' is stopped, everything is stopped. It is going to last for many weeks, months, or years ... It takes time before you are able to appreciate life again.
"What happened to us as victims makes us bigger and stronger -- not immediately of course -- but after a good healing and understanding and support, we become stronger and it's a defeat of the terrorists."