i know EXACTLY what you're going through. The solution is simple.
You have to feel better than everyone else.
For instance, in my old beat up Honda if I did something stupid on the road (like entered a parking lot through the "exit") I'd get all freaked out and have to go and hide because I thought everyone was laughing at me. Now, in my Mercede's, I just think "screw them! I'm in a Mercedes, I can do whatever I want!" Of course, now I am slightly in fear that they will discover how much I payed for the car and that will set me right back at square one... well, except I'd still have a really really pretty, fun to drive, and safe car.
So, if you feel like you're better than they are, you will not be worried about screwing up because even if you do screw up it's okay because you have the right to be stupid.
Now, it's important to note that this is all in your head. People will probably still laugh at you just as much. But, they probably aren't laughing at you nearly as much as you think. Actually, most of them are probably thinking "my god, I'm glad I didnt do that! That would be horrible! Poor bastard," but then when you are better than they are then they start to think "stupid rich bastard, look at that cunt... he's such an idiot." But, why do we care what they are REALLY thinking? All we care about is what we PERCIEVE them to be thinking.