It is a familiar feeling for the 22-year-old. Just last week he returned to Glasgow after a training camp in Germany - adding to an annual itinerary that also includes trips to France, Belarus, Albania and Serbia - yet his bags are already packed for another journey.
That recurring scene was played out on Tuesday, the fighter having joined his Great Britain team-mates in London before boarding a plane bound for Kazakhstan and the AIBA Boxing World Championships. "And me just a wee boy fae Govan . . ." says the middleweight, considering his circumstances in the minutes before his flight to Astana is called. Brown confides that, sometimes, he has to remind himself that this is his life, that he is paid a salary by GB Boxing to fight full-time; that he has been all over the world doing something he loves.
Yet the culmination of his dreams could come somewhat closer to home next summer. Indeed, were the Glaswegian to peer out of a window in his home, he would see the newly-opened SSE Hydro, the venue for the finals of the boxing competition at next summer's Commonwealth Games. "Aw man, I'm getting goosebumps just thinking about it; I grew up just two minutes away," he says. "Delhi was a magic experience but this will be something else."
He was just 18 when he travelled to India as part of Team Scotland but that did not compromise his performance. Then competing in the welterweight division, Brown outperformed expectations by first overcoming Kenyan Rayton Okwiri, then upsetting the London Olympian Custio Clayton of Canada to reach the quarter-finals before losing to English silver medallist Callum Smith. Such success, combined with being in the athletes' village with some of the biggest stars in sport, made it the most rewarding experience of his life but even that will be eclipsed by events next summer.
"I was just a kid then but I'm a different fighter now," he insists, referring to more than just his step up from the 69kg to the 75kg division. "Basically, there's only one thing I'm going for in front of my hometown crowd and that's a gold medal. It needs to be like that; standing on the podium hearing the national anthem. There's a pressure that comes with that but I think I'll thrive on it at this stage in my career. A few years ago it might have been too much for me, and I might have buckled, but now I'm experienced at this level and once I step into that ring, it's just me; nothing else around about matters."
Brown's determination to meet those expectations will face stern resistance. The middleweight division will be strong in Glasgow, with those such as Vijender Singh - the feted Indian fighter has been to the last three Olympic Games and won bronze in Beijing - and England's Anthony Fowler among the medal favourites, with an unseeded draw meaning that the Scot could suffer the misfortune of having to face either man in the opening round. As befits a man from Govan, though, Brown blithely refuses to be fazed by the prospect.
Instead his focus is fixed on the impending challenge in Kazakhstan, given that a solid showing in his first major global event should effectively confirm his place in Glasgow. His relatively recent ascension to the middleweight division means he has not earned enough points to be world ranked, let alone seeded, but that is not stopping him from nurturing lofty ambitions ahead of the competition, which begins on Monday.
"I'm expecting it to be tough but I want to get myself a medal," says Brown, who showed up well in the European Championships earlier in the year. "I know if I stay switched on and focused I can do it. Sure, I could draw one of the eight seeds but that doesnae bother me because I'm definitely as good as those boys. The way I'm looking at it is that I need to win six fights to win and four to get a medal."
Such confidence is informed by the impressive manner in which he has adapted to the middleweight division. The decision, taken at the start of this year, was pre-empted by his difficulties in making the lower weight and Brown is feeling fitter, stronger and quicker as a consequence. "I was always quite big for a welterweight anyway, naturally outside the gym I was sitting at 74-75kg," he says. "It was killing me trying to make 69kg. I was in a bad way, going to tournaments feeling crap, catching colds and feeling ill because I was draining myself and my immune system was low. It didn't make sense, so I had to move up. It was just about getting in the gym and working on my strength, which was an easy enough process."
It was ever thus for Brown since he first wandered into a boxing gym at the age of 10. His older brother, Jackson, had gone along to the local club at the Palace of Art one evening and, upon his return, was besieged with questions by his inquisitive sibling, who was desperate to experience it for himself. Jackson eventually relented and took Aston along the following week. "I can remember that first day as if it was yesterday," he says. "I saw everyone sparring and hitting bags and my eyes lit up. I just had a great feeling about it and I've never looked back."
Even the lure of drink and women could not divert him from his course. "I never got involved in any of that. Not in a weird way; I just wanted to box," he says. "If I wasn't boxing, I wouldn't be doing anything else. I'd probably just be working in a job I didnae really enjoy. Instead, boxing has given me an opportunity in life to follow my dreams."