Shawn Mendes, left, and Camila Cabello accept the award for collaboration of the year for "Señorita" at the American Music Awards on Sunday, Nov. 24, 2019, at the Microsoft Theater in Los Angeles. (Photo by Chris Pizzello/Invision/AP)

Camila Cabello has praised her boyfriend Shawn Mendes for his "caring and beautiful heart".

The 22-year-old singer has thanked her boyfriend for his support following their performance of 'Senorita' and win for Collaboration of the Year at the American Music Awards on Sunday.

She shared a series of photos from the event on her Instagram account and wrote: ""I love u @shawnmendes thank u for being so there for me yesterday and every other day, u have the most caring and beautiful heart in the world !

"Thanks to all our fans for voting , we love and appreciate you guys so much and are so thankful for you [heart emoji].(sic)"

Meanwhile, 21-year-old Shawn share a photo of the couple picking up their award on his own Instagram account and praised the former Fifth Harmony singer for being an "unbelievable human being".

He wrote: "@amas thank you everyone thank you so much!! [heart emoji] also @camila_cabello i admire you so much you unbelievable human being thank you for being you [heart emojis] we love u guys (sic)"

The couple have only been dating since July but the 'Havana' hitmaker recently admitted she has had feelings for Shawn since they first collaborated together on their 2015 hit 'I Know What You Did Last Summer'.

She said: "During 'I Know What You Did Last Summer,' I really bonded with him as more than a friend. I think he did, too, but we were both really young, and he was experiencing the pressures of his career.

"I don't think we knew what to do with those feelings. It was this awkward thing where we both liked each other, but we weren't together. It was just weird."

Following their 2015 collaboration, the pair "didn't spend as much time together", until they were reunited earlier this year, when they worked on their June 2019 track 'Señorita'.

And during the recording process, Camila admits her feelings for the musician came flooding back.

She added: "Our paths just didn't cross in that way romantically until we started hanging out again and writing. For me, it just brought it back."