Hanging out with a guy 5 years younger than me?

So there was this guy I used to work with. He was 19 and I’m 24. I left that job but he still talks to me every now and then. He was always very friendly and respectful to me and seems kind of timid. He asked me if I was free this Tuesday... he’s been asking me every few months if I was free but I haven’t been answering because well, he’s 5 years younger. He also said he wanted to take me out to dinner and a park or something a few months ago and I never responded...

I turn 25 in 3 weeks and I’m not sure if he’s still 19 lol he might be 20 now. I feel really creepy and weird hanging out with a guy 5 years younger as I’ve only dated older men or men my age. I almost dated a guy 2 years younger than me but that still felt weird to me?! Like he just started college in January and I just graduated in May. Is it weird? I feel like if it was the other way around it wouldn’t be?