When you're in new or awkward situations or when you imagine that there are rules of behaviour that everyone else seems to know but you. Terrible isn't it?
It is quite possible, with a little effort, for everyone to develop really effective interpersonal skills.
You can learn how to deal with the feelings that arise in difficult situations instead of being overwhelmed by them.
Nobody lives a feeling free life.  
Everyone has moments where they feel less than capable.
The trick people with good interpersonal skills have learnt is to identify which feelings get in the way of connecting with others.
Then they have practised new ways behaving when they find one of those feelings coming on.
A little time spent working on you interpersonal skill set will pay huge dividends.
In time you'll find you'll be able to work well in any communication arena.Interpersonal skills are all about working with other people. They include being able to support and encourage others, being able to give and receive constructive criticism as well as being able to negotiate.