i've been to about 3 concerts, all standing. a few suggestions:
It sounds silly, but make sure u don't smell of b.o. I made the mistake of rushing to a concert without showering, it can make you feel quite self-concious if u lift ur arm up and smell that smell when ur standing in a crowded area. Towards the end of the night i think people near me had distanced away to form a circle around me, don't blame em
Some alcohol can improve ur concert experience drastically, u sound as if u mite need it if u don't like being around crowds of people. Drinking some beer helps me stop feeling so stiff and self concious, and combined with loud music i love, i don't really give a damn about the people around me anymore. a great feeling!
If ur having trouble hearing certain instruments, don't hesitate to move around a bit. where ur standing can cometimes make a huge difference to the sound. also, if your so close to the speakers that when the music starts playing u can "feel" it, mite want to try and move back a bit. on one occassion i was standing almost at the barrier rite in front of a speaker, and at the end of the set, everything sounded pretty distorted. the lead guitar sounded like one constant whine lol. i suppose ear protection would help this problem, although i've never tried it out. also, try and get a space in the centre of the floor space for best sound balance.
hope this helps