New pain

 Hi everyone. I am 20 months post op. I have developed a small bump under one of my scars that has been tender to the touch and slightly painful. I was hoping it would go away on its own but it has been there for a few days. I called my surgeon but I haven't heard back yet. 

My worry is that is a hernia. 

What do you think?

I'm not a professional but it doesn't sound like a hernia. Maybe just scar tissue?