Tom Allen was stuck at home and feeling trapped, so he went for a bike ride. He ended up camping on a deserted beach in Yemen, surrounded by crabs and dreaming of an Iranian girl.

In 2006, Allen cycled from his sleepy Northamptonshire village with a tent, a camera and a budget of €5 a day. Three years, three continents and 32 countries had passed before he cycled through the English countryside again, returning with an Iranian woman called Tenny for company.

"I committed myself to cycling round the world without a map," Allen says. "I wasn't interested in cycling, I had never toured on a bike before, or travelled far. I didn't know what I was doing, I didn't know if it was possible. I was a beginner in every sense of the word."

Allen was 23, a recent graduate working as a freelance web developer.

"I couldn't have been more miserable," he says. He felt scared at the prospect of sitting in front of a monitor every day. "I didn't feel in control of my own decisions. I had a horrible feeling that other influences were steering my life, that the world had more to offer. I wanted to be completely independent, and I wanted the self-propelled nature of being on a bike."

Allen started out with two friends, but they gave up within weeks. So he continued "a lonely, solitary journey", cycling across central and eastern Europe, central Asia, the Middle East and the north-eastern spine of Africa; Egypt, Sudan, Ethiopia, Djibouti. Along the way, he haphazardly shot 300 hours of video that show him running out of food and eating a mixture of spaghetti, peanut butter and jam, choosing a road forked between Damascus and Baghdad, contracting malaria in Sudan and realising he had met his future wife.

With the help of BBC director James Newton, the footage Allen shot on the road has been shaped into a feature film titled Janapar, Love on a Bike (janapar being the Armenian word for journey) whichhas recently been released online, while Allen has crowdsourced the funds needed to self-publish a book of his experiences.

"I grew to love being on the road, because you don't think about the big picture," he says. "Almost every journey is about getting from one place to another, but travelling by bike is purely about what happens along the way. You live day-to-day, you don't need to worry about money, you just think about what to eat and where to sleep. You do whatever feels right at the time, and you realise the world is a lot less threatening than it might appear."

That's not to say the journey was easy. The lowest moment, Allen says, was arriving in Sudan and realising the next town lay across 1,000km of desert – and he just had a compass for guidance.

"I had a limited amount of water, a limited amount of food, not much shelter and a sandy track for a road. I've never felt so vulnerable or helpless, before or since."

At this point, Allen was thinking of Tenny, a 28-year-old Iranian graphic designer he fell for in Armenia. He lived with her for eight months, but was getting itchy feet. So he convinced her to cycle on with him, even though Tenny hadn't cycled since she was a child and had never travelled beyond her native Iran and adopted home of Armenia. Their first trip, they decided, would be to Tehran, the capital of Iran, to meet her parents.

"It was extremely foolhardy for us to even try it," Allen says. "She agreed to cycle with me out of passion rather than pragmatism."

"When you meet someone and you realise he's the person you've always been waiting for, it allows you to make very big decisions," Tenny says. "But cycling was completely new to me, and the whole idea was pretty confusing. He convinced me that cycling to Iran would be a great idea, and I remember thinking it was something I can do to be with him. But by about the middle of the first day, I wanted to go home to Armenia."

When they reached Tehran, her parents went berserk.

"We've had an evening of shouting, crying and being told in no uncertain terms there is no way on this planet we are going to continue the journey," Allen says in the film. "Everything I hoped for us has just been mercilessly blown away."

"My parents were very upset with us," Tenny says. "They were upset we did it in secret, and they were very worried about me. Part of the challenge was knowing I was doing it without my family's support. But I felt I had to make a decision for myself."

Tenny's parents grew used to the idea. Tom and Tenny got married in Armenia and cycled back to the UK. They now live between Norfolk and Armenia and work as professional "adventure cyclists", still spending months on the road. Yet Tom is more settled now, more willing to spend eight hours a day in front of a computer. "I know what I'm doing now," he says. But, reflecting now, what did he learn from the experience of naively doing it in 2006?

"A journey like that can go on and on and on. It can feel there's no end to it. I packed in everything to do it, so it could be scary," he says. "But you'd be surprised how quickly you realise there isn't supposed to be an end – just the present moment, just the next bend in the road - that there's always a road that hasn't yet been taken, but that's no reason not to take it. I'd encourage anyone to try it."