Should I keep saying Salam or avoid it?

Assalamu alaykum, I’ve been stressing over something small but it’s been bothering me and I’d appreciate any thoughts. I (f20) work at a shop in a mall. I’m naturally friendly and usually greet other workers I see, even if we’re not close, because it comes naturally to me. A couple months ago I had a short chat with one of the mall security guards - he asked about my background and mentioned he’s from the same country. Then, a week later, a stranger waited outside my store for about 30 minutes after closing when the mall was shut. The same guard saw it but didn’t do anything, so I later called security to report the incident. After that I saw the guard a few times. I said Salam once when he walked by, and he also said Salam to me another time. But a few weeks later, when I was leaving the mall one night I said Salam to him as he stood by the door. He paused, looked really tense and replied awkwardly, then cut himself off. It felt like he suddenly switched from normal to very nervous. I couldn’t stop overthinking why he acted that way. Growing up in the West, I’m not always sure about certain cultural or gender norms from back home, so I wondered if I’d crossed a line. That interaction made me uncomfortable and I began avoiding him at work because I didn’t want another awkward moment. Today as I was entering the mall we made eye contact. He looked like he might acknowledge me and seemed calm, but because I still felt weird from before I avoided looking and walked past. He looked surprised. Now I feel guilty and worried I came off as rude, which is not like me since I try to be kind and respectful. This has stuck with me and I’m anxious about what to do if I see him again. Was it wrong to say Salam in the first place to a man I barely know? Was I rude to ignore him today? How should I handle similar situations Islamically and practically, especially since this is my first job and I’m still learning workplace norms? Any advice on how to stop overthinking, what would be the appropriate way to greet or respond in the future, and whether I should try to make amends would be really helpful. JazakAllahu khair.