I (27f) have a crush on my coworker (25m)

I’m in this weird area in my life where I’ve never dated anyone before, and I have only ever liked a few people in my life. I’m talking about getting actual butterflies in your stomach kind of like. It might seem sad, given my age, but I don’t mind waiting for the right person to come by. I’m just afraid I missed my chance with a guy I like.

I started to develop a crush on my coworker a couple months ago when I made a comment that, reflecting back on it now, was kind of flirtatious (even though I didn’t meant it like that when I said it). Since then, I started noticing things he would do around me. He would linger around too long. Stare at me when he thought I wasn’t looking or turn to look at me when we walk by each other. We work in different areas so we don’t really see each other that often, but sometimes he would come over to me just to ask for mundane things like a pen or rubber band. Recently, he started sitting across from my usual lunch spot.
But I’m so inexperienced when it comes to love, that I can’t process how to feel and I end up wanting to run away whenever he’s around. I can’t stop physically shaking when he’s near me. I can’t look him in the eyes. I forget how to talk that I’m afraid I’ve made it so awkward to talk to me now. I messed up twice on a task that we had to do together, that I felt so embarrassed because it was my own mistake not his. It doesn’t help that he’s really handsome that I’m sure other people also like him. But I’ve never had someone stare at me so much before. Maybe I’m overthinking this too much and that’s just the type of person he is.

I’ve been waiting for him to say something because I don’t want to assume the things he does means he likes me. I’ve made that mistake before because I’m bad at reading people. But with how things are right now, I know the only way I’ll feel better (and to stop screwing up at work) is if I ask him. I’m scared but I’m prepared to be rejected. I just don’t get many private moments with him to finally ask him.

TL;DR
Never dated, made a flirtatious comment one time and developed a crush. It’s awkward now because I overthink and I’m scared.