Jonathan and Charlotte filming promotional material for their album in Florence

As the audience erupted into cheers and glitter rained down on to the stage, two school friends were crowned runners-up of Britain’s Got Talent 2012.

Jonathan and Charlotte's album, Together, is out on Monday

In a blur of photo shoots, interviews and television appearances, the talented singing duo, who shot straight into the final in May, became overnight stars.

For Jonathan Antoine, of Hainault, and Charlotte Jaconelli, of Chigwell, the past four months have been an “amazing whirlwind” ahead of their album release on Monday.

The former West Hatch High School, High Road, Chigwell pupils said doing the show was “absolutely brilliant,” despite losing out to winners Ashleigh and her dog, Pudsey.

Charlotte, who celebrated her 17th birthday last week and has previously performed at the Kenneth More Theatre, Oakfield Road, Ilford, told the Recorder: “We are so excited about our album, Together, and when we first saw the finished version we went crazy.”

Jonathan, also 17, said: “So much has happened over the past few months, it’s been ridiculous. It is so hard to sum it all up.”

The pair, who went straight into the recording studio following the show’s final, were asked to bring in a list of songs that meant something to them for possible inclusion in the album.

“Luckily most of the songs we suggested were the same as the ones the label wanted, so that worked out well,” said Charlotte.

“Our families have been so happy for us, although my sister seems most excited about the fact I am signed to the same label as One Direction, even though I’ve never met them.”

Jonathan added: “We have been through a lot and it is so great to have support from our friends and family; my mum comes everywhere with me.

“Making the album has been brilliant and much better than we expected, but it has been a lot of hard work and took about six to seven weeks to finish.”

The singers, who live with their families, were first paired together as part of their GCSE music exam two years ago and they sang at the wedding of their teacher, Ginette Brown.

Charlotte said: “We were first put together by our teacher and everything kind of fell into place. After our first performance together at a school concert, we realised we worked really well together.

“When we look back now we realise how much we have improved and perfected what we do.”

They started off their singing careers differently as Charlotte attended stage school from a young age, while Jonathan did not begin singing until he went to secondary school.

He said: “I got a really positive reaction when I started singing.”

Teacher Mrs Brown said: “When I asked them to sing at my wedding in August [last year] they were both really emotional. It meant a lot to my husband and I, and they knew it was a big deal.

“The song they chose for the final of Britain’s Got Talent, The Prayer, is the one they sang at my wedding.

“When I joined the school in 2007, my colleagues and I noticed their talent very early on, especially Jonathan.”

Jonathan and Charlotte went to Florence to shoot promotional material for their album – a trip they described as “incredible”.

Jonathan said: “Previously I had never been further than Calais, but Italy was just gorgeous.”

In their original audition for the popular TV talent show, judge Simon Cowell, who described Jonathan as “unbelievable”, suggested he should go solo.

Jonathan said: “I stand by what I did. To stay with Charlotte was one of the best decisions I ever made.”

Charlotte added: “It was really upsetting at the time but I think in a way it backfired on him [Simon] as it drove me to prove myself.”