Lady Gaga made Justin Timberlake “feel old”.

Gaga admitted she was a huge fan of Justin's former group *NSYNC when she was a teenager.

“She told me when she was 14, she sat outside a radio station with *NSYNC painted on her cheek,” Justin said.

“She said, ‘I hope that doesn’t make you feel awkward.’ I said, ‘Hell no, that makes me feel old.’ ”

Tp be fair, Justin is older than Lady Gaga, but he's not that old!