I just find social situations awkward and don't know what to do. Normal people seem to not have this problem. Here is an example:

There is this girl at the gym who works at the front desk. She is really friendly with me even when she is not on the clock and is working out and sees me there. I hadn't seen her on a few weeks. Today as I was leaving I saw her at the front desk. She was folding towels and talking with a coworker. As I was walking towards the area, I notice her look in my direction. I waved and smiled. But she apparently didn't see me because she didn't return my respond and she turned back around, looking out towards the entrance. I wanted to say greet her on the way out and I actually had it planned what I'd say, I had been preparing for this possibility before even seeing her there. But then with her coworker there talking to her I just felt it would come out very awkward if I walked over and said something to her. And even simple things like the way she is positioned facing away from me makes things it more awkward for some reason. I feel like when I try to talk it often ends up coming out in a weird way so in these situations I feel anxious that this would happen and she would think I'm a weirdo. So I ended up just walking by without saying anything. She was swiping someone in, but then when I was halfway out the door I hear her say "byyyye" in a friendly way. I am not sure if that was meant for me or for the guy walking behind me. But I feel like it may have been rude of me to just walk out without saying anything to her. This is the kind of thing I am talking about.