WIB creepy if I asked out a store clerk?!

This is completely new territory for me! I've been single for almost a year atp, after a 3 year partially LDR ended. Never dated before that. Never been on a proper date really! Never had a crush on someone before (I do consider myself asexual, look it up if you're unsure what it means!) but...I think I might now!! I'm also in a place where I feel a lot more sure of myself.

Yesterday morning I was in a furniture shop and bought, well, furniture. The guy helping me was very nice, and I thought he looked cute too! And he seemed to look at me as well in a different way than the customer he helped before me (that or I'm insane!).

I've not been able to let him go since! I keep thinking of him. We had a nice little chat. Then when I exited the store I saw him again down the hall, and I went to put my hair behind my ear as I talked to my mom, and I saw him do a sort of wave then hurriedly put it back...And he quickly averted my gaze! I realised he thought I'd waved to him. I think that looked cute lol.

Anyways, I can't stop thinking that I want to go back and, if he's there, somehow strike up convo and just...ask for a coffee or smth!

But would this be WILDLY inappropriate?! Ik it's his job to be nice to me!! But he seems so sweet, and looks cute too! And if he says no, itd hopefully make him happy to have been asked out.

I'm very prepared for a no. And worst case...I will just avoid that store for a long time lol. I barely go there anyways, but need to go back to check for a sofa again anyways. Just so so worried I'll make him uncomfortable, or if it's entirely wrong to consider actually doing this.