The moment, when it came, was really powerful. Last Thursday night, in our GB Boxing team room in the Olympic village, it finally hit me. This is real. I am about to fight in the Olympic Games and my hopes of winning a medal, with gold being my favourite colour, begin now.

We had been in Tokyo for 10 days, staying in a hotel for the first week before we moved into the village and it had all felt a bit surreal. I had this weird feeling this was just another training camp and I couldn’t switch on totally. It was like being in some kind of limbo where you are waiting for something to happen and kick-start everything. Last Thursday night, around eight o’clock, it happened. They made the draw for the boxing competition and the coaches came in with the news for all 11 of us in the GB team. They went through it fighter by fighter and when it came to me it was like the world suddenly stopped.

“Caroline,” they said, “you’ve got Kosovo on Tuesday.”

I’ve been to so many tournaments as a junior, and I’ve won the World Juniors and the Youth Olympics, and it’s always the same. You wait and wait for the draw to be made and as soon as you find out who you’re boxing in the first round your heart drops a beat and you’re like: ‘Oh my God. This is real.’ For the next 10 seconds you just think: ‘Wow.’ It’s a feeling like no other. You are so locked in the moment and your stomach starts churning. But then it all calms down and you put yourself back together.

This is what you’re here to do – to fight. Everybody out here is boxing at a very high level and that makes it even more exciting and interesting. We’re all fighting for a medal, and we all want it bad. So I can’t wait for it to start.

The draw is so strange because, unless you are one of the four seeds, you could fight anyone in the first round. I never lost a single fight as a junior but my first adult tournament was the Olympic qualifiers in March 2020. I won my opening bout easily and then Covid changed everything. The tournament had to be cancelled. I lost over a year of competition and my next big fight was in the European qualifiers in Paris this June. I beat the world No 2 Mira Potkonen and made it all the way to the finals. I was gutted to lose to Kellie Harrington, from Ireland, who is seeded No 1 in Tokyo.

Caroline Dubois after her qualifying victory
Dubois has high expectations for Tokyo 2020 after her success as a junior boxer. Photograph: Dave Winter/Inpho/Shutterstock

Kellie is 31. I am 20. She has been a world champion and must have had over a hundred bouts as an adult. I’ve had 50 unbeaten as a junior and I was so excited to meet her in the ring. She won the fight but I definitely want to avenge that loss in Tokyo. I am not used to losing and I hate it. So I would love to fight her again and beat her this time. She is a great champion and it would be really hard – but if all goes well we will meet in the semi-finals.

At this stage my main focus is on my opponent on Tuesday. Anything can happen because boxing is crazy. How many people thought I would beat Mira? She beat Katie Taylor at the last Olympics so lots of people thought I couldn’t win. But I did. Now lots of people will think I’ve got an easy fight on Tuesday. Donjeta Sadiku is from Kosovo and in the European qualifiers she lost to Agnes Alexiusson – the Swedish woman I beat in the semi-finals. So on paper you might think this is already decided. You would be wrong.

I actually think Sadiku is very talented. She is older and more experienced than me and when I’ve watched her I’ve thought: ‘Hmm, she’s pretty good.’ I was a bit shocked the Swedish girl beat her so it will be a test. But of course I expect to win and I would then face Rashida Ellis, an excellent American, who has a bye into the last 16.

I sparred against her in Colorado at the start of 2020. Ellis had won bronze at the world championships in 2019 and so, that day, I was a nobody, a real underdog, in adult boxing. But I loved it. It was a very technical spar, smart and tricky, tit-for-tat. It was lots of fun and she is seriously good. But I believe I’m better.

If I win that I’m in the quarters and one bout away from winning a medal. But that would not be enough. I want to go all the way. I did not sacrifice everything all these years I’ve been boxing, cutting weight and training so hard, to settle for a few good performances. I don’t just want a medal. I want the medal.

All that can wait for now. I am thinking only of beating Donjeta Sadiku on Tuesday. That absolute focus means I haven’t stressed about Covid. I’ve heard about other athletes being so worried they’ll catch it and miss out on the Olympics. But there’s no point stressing about something that’s out of our hands. We can only control our boxing abilities – our sharpness, our fitness, our mental preparation. That’s all going so well and I’m sleeping easily at night.

I’m sharing accommodation with my three teammates – Lauren Price, Charley Davison and Kariss Artingstall – and the mood is great. We have such a talented team, alongside the seven guys fighting for GB, and I think we’re going to have a special Games. But all my attention is on my Olympic debut. I am determined to make it an unforgettable start.

Caroline Dubois is writing for the Guardian during the Tokyo Olympics.