You need not to be like that at all.
All you need to do is to put a nice & lovely smile on your lips when eying people.
If you cannot eye them,look at the tips of their noses.You will seem like looking at them.
When you do presentations,make sure you talk slowly,take a deep breath after each sentence said,eye all the audience,and try to make fun out of it as applicable or when & where possible.
You need to like yourself a bit more than you do now.Remind yourself with the fact that people around are coming to you,calling you,seeking you.which means you are a likable person.
Just socialize with people around you,and make a habit of it.
One thing to remember:PEOPLE WILL NOT BITE YOU :-)