Distraught, he locked himself in the toilet and phoned his mother.
In between sobs, he then told her how he was being bullied by his peers and superiors and that he was unable to cope with his duties in the army.
But more worryingly, he threatened to end his life, prompting his parents to bring his condition to the attention of his superiors and the army.
Bryan (not his real name) has Asperger Syndrome, a form of autism.
He was enlisted as a full-time national serviceman (NSF) in 2012, but after a difficult year, he was exempted from the service in March last year.
Last week, his father wrote in to The New Paper after reading about Private (Pte) Ganesh Pillay Magindren, 23, the NSF who was found dead at the foot of his Sengkang condominium last July. (See report right, below.)
"I wanted to share that what my son went through was similar to Pte Ganesh," he told TNP in a subsequent phone interview.
Bryan's father first noticed unusual behaviour in his son in kindergarten.
"I thought something was wrong with him when he would just sit there and not interact with other children," he said.
Bryan was taken to a psychiatrist, who diagnosed him with Asperger's, said the father.
"He's not able to socialise normally, has trouble articulating and has compulsive behaviours.
"But other than that, he was normal. He's not mad. He even took his A levels and did well," he said.
The father said he had initially encouraged his son to go through national service.
"Bryan was originally very excited to be enlisting. I also thought it would be an opportunity for him to become more independent and learn how to be around people," he said.