Johnny discovered he had a tumour in his brain after his girlfriend Tahnee Sims rushed him to the hospital when he complained of a severe headache.
"I was just at home and I had a headache, but everyone has headaches and you never think much of it," he tells Who Are You podcast host Pete Timbs.
"It had been ongoing and it just got worse and worse. It got to about 4 or 5 in the afternoon and I couldn't speak, I couldn't communicate with her [Tahnee] at all."
That's when Tahnee decided she had to take Johnny to the hospital. At first he was told it was just a migraine, but was told to stay overnight for testing. The next morning doctors rang Tahnee and revealed that her boyfriend had fallen into a coma, had a brain tumour and would have to undergo emergency surgery to remove it.
The singer also revealed that he has big plans for 2019.
'I've got lots of big plans,' he said of 2019. 'I've got some new music coming out, the next song that I'll release is called Broken Glass.
'It's kind of about my experience over the last two years. Just dealing with everything and what I've been through and the people who have supported me.'
