Is it alright I love looking at pictures of my boyfriend from when he was a teenager?

I have always found my boyfriend to be an attractive guy. When I first went to his house, I saw a few pictures of him around as a teenager like graduation pictures and such. He is in his late 20s now so when I saw those pictures I thought he was a really good-looking teenager.

I find myself looking at his teenager pictures a lot though, more often than I look at recent pictures of him. I think he was such a little babe and had a nicer body then as well. Is it normal or alright that I love to look at his teen pictures all the time, and I like knowing he looked like that at one time? I feel sometimes like maybe it's strange I look at them a lot. I want some opinions.

I think it's probably alright, I mean it is not like I am looking at other guys. I am looking at my boyfriend, just pictures that are like 10 years old.

I love to imagine that we went to school together, (we didn't) I just like thinking about him as a teenager and what he was like and what he looked like. Is this normal or acceptable? Thanks so much for the answers, it's appreciated!