When a guy can't look another guy in the eye long or don't feel comfortable looking another guy in the eye long...what does this mean?

It may be that your gay, if not that's ok it could be you might just be socially shy, but most guys if you stare at them long they might think you are abit more intrested then you should be. So look at them and look away once in a while but let them know u are still listening.