I think it could be both.
I suffered from extreme social anxiety and awkwardness for a long time and had to carefully study people who did well socially to learn what was considered appropriate. Now I can more naturally engage in conversation with people, but it is a learned skill and not innate. Sometimes thinking about what you are about to say a little less will make the conversation flow more easily. (I still hate small talk too though...)
The empty void feeling indicates depression to me. I know when I feel really bad I get a cold empty feeling inside and it feels like I'm falling into it. I don't know how you overcome that, but trying to find things that you can enjoy or distract you might help you get started.