Shy or social anxiety?

Whenever I’m out in public shopping etc, I always get super shaky and worried and I feel like everyone is watching me and if I need to go down a certain aisle to get something and there’s another person there I’ll purposely wait until they’re gone. I also get super paranoid I’ll see somebody I know and have to talk to them. Whenever I’m paying I get super anxious as well. Is this social anxiety or just me being antisocial ?