^This woman offers great advice. I'd also like to add that it will be much easier for you if you eat something that's not very messy. Finger foods, like grapes and cheez-its as ASG mentioned, will give you less reason to be embarrassed because you won't have to worry about sitting there looking like a fool with spaghetti sauce smeared all over your face.
This is something I have to remind myself frequently, and it might help you too in this situation: WE ARE OUR OWN BIGGEST CRITICS. Nobody else really cares what we do, it's our own awareness that freaks us out so much. You'll be alright.
