Small talk and social interactions

I don’t know if this is the right subreddit to discuss this, so sorry if it is. But I wanted to talk about my experience with “greeting people”, I think? And I'd love to know if someone else relates.

I’ll set the scene. For example, I am at the mall and I see someone I know, like a friend I don't talk to a lot. I get scared. Like, I feel this sinking feeling in my stomach because..I will have to interact with them. And If I don’t, I'll be seen as rude. Most times I act as if I didn't see or recognize them and walk past looking at my phone or something. I don’t know what it is about just saying hi and making small talk, but I just get really scared and uncomfortable, like MADLY. I can recall some (most.) instances where I just stood there awkwardly, staring at them (and the ground) for 2 minutes and then said bye before walking off. It is, for some reason, EXTREMELY exhausting. Like 10 seconds of small talk feel like a 10 hour shift. And no matter what, I feel like I'm the only one who experiences it…Like this? As in, I feel like if I spoke about it, I think it’d be called social anxiety, but I don’t know if it’s that, it’s more the thought of the small talk which floors me. I can’t do or handle small talk for the life of me, and I feel most people I know think I'm rude because I just ignore them instead of saying hi. Does someone else relate? Would love some advice if you have some.