A fan of Liam Payne exclusively tells PEOPLE that she had a few interactions with him leading up to the One Direction member's death, and there was "nothing strange or unusual" about his behavior.

Liam Payne was having the time of his life at former One Direction bandmate Niall Horan's Buenos Aires, Argentina, concert stop days before his death, as seen in a video. Liam's girlfriend, Kate Cassidy,

Niall Horan has posted a heartfelt tribute to his One Direction bandmate Liam Payne, who he was reunited with recently at his Buenos Aires show on Oct. 2. "I'm absolutely devastated about the passing of my amazing friend,