"It was completely the wrong instinct," the Scottish DJ said during an interview with GQ about how he reacted to Swift revealing that she penned his song with Rihanna titled "This is What You Came For."
"I was protecting what I see as my one talent in the world being belittled," he continued. "It felt like things were piling on top of me and that was when I snapped,".
Harris had tweeted after Swift's songwriting reveal, "Hurtful to me at this point that her and her team would go so far out of their way to try and make me look bad at this stage. I figure if you're happy in your new relationship you should focus on that instead of trying to tear your ex bf down for something to do."
The pair called it quits in June 2016 after dating for 15 months.
"The aftermath of the relationship was way more heavily publicized than the relationship itself. When we were together, we were very careful for it not to be a media circus. She respected my feelings in that sense," Harris said of their time together and before admitting that his songwriting rant was "a result of me succumbing to pressure."
"It took me a minute to realize that none of that matters. I'm a positive guy," the 33-year-old said. "For both of us, it was the wrong situation. It clearly wasn't right, so it ended, but all of the stuff that happened afterwards."