“Playing by instinct was always one of my strengths in the past, to just play football on the pitch and not to think about things a lot.
“I think also, when you come here with a price tag on your head, everybody expects you to play very good, and if you don’t play very good they start talking.
“But after six months it was getting better.”
The German rounded City goalkeeper Ederson before tapping the ball into the empty the net to score the only goal of the game just before halftime as the Blues clinched their second European Cup.
While the finish may have looked straightforward to onlookers, Havertz admitted a series of negative thoughts went through his head as he faced the open goal.
The 22-year-old was fully aware that a miss would have immediately transformed him into meme material and left him open to ridicule on the internet and on social media.
The goal against City in Porto was the perfect ending to a relatively difficult debut season in the Premier League for the German, a £70 million signing from Bayern Leverkusen.
Havertz took his time to find his feet at Stamford Bridge, starting just 18 of his 27 Premier League appearances for a return of four goals and five assists.
The German had a bigger role to play in Europe, starting nine of his 12 Champions League appearances but the winner against City was his only goal in the competition.
So far this season, Havertz has started four of his league appearances but was an unused substitute last weekend, as Chelsea beat Southampton 3-1 to go into the international break top of the table.
The former Bayer Leverkusen man conceded he needed some time to adjust to life in a new environment but insisted he now feels completely at ease in West London.
‘Of course you get used to it when you play some games, when you have some matches, when you are here in England for some months,’ he said.
‘It’s a different type of football, but I think you get used to it and it was the same for me. After six months it was easier for me and then I settled in very well.
‘I feel very good on the pitch and you are more relaxed on the pitch to play. Then, of course, it was getting a little bit better and now I’m used to it and I’m feeling very good.’