Would you be upset?

Basically if your long term partner was watching old videos of him and another girl when they were like 18?

So like he’s 26 now we have been together for 5 years. He used to play guitar when he was like 18, and him and a girl he was with at the time made a song called “ we belong together” where he was playing the guitar and she was singing I guess they made this song together like lyrics and all . He uploaded it to YouTube back then and I saw he was watching that this morning. Would that bother you? Idk if I’m just overly sensitive ( cause I am that ) but I don’t wanna make a deal out of it if I’m just being weird. Lol