Is my Rainfords Goby sick?

[jphong]

HI everyone, I need some help with my Rainfords Goby. Last week I noticed that there was a purple-ish color under the skin at the left gill. Today I took a closer look and it looks like there is a small bump forming in the same area. Can anyone give me some advice on what to make of this?

See pic below.

Thanks for any help I can get

[IMG]file:///C:/Documents%20and%20Settings/jphong/Desktop/Saltwater/fish/Sick%20Rainford/New%20Folder/Picture%20018%20%28768%20x%20576%29.jpg[/IMG]