two words for you, RESCUE REMEDY!!
it calms you down no end it works absolute wonders. i have huge oral exams on at the moment and im flying them... cos im calm and relaxed.
it costs about 8 eure in all good chemists. pop 4 drops on your tongue about a half an hour before ur due on stage and put 20 or so drops into a bottle of cold still bottled water. sup the water for about 2 hours before hand and i can guarentee u'll be as cool as a cucumber. the only downside is that it kinda smells of whicky and kinda tastes like it too but i swear by it.
try it... it reallly works. theres no side effects.
it works too if you cant sleep at night, pop a couple of drops on you tongue and off you go.
trust me
best of luck