Scared of vomiting? Someone please help :'(?

waa. I've had this phobia ever since i can remember. i have some weird anxiety disorders. and yeah i stress out heaps and the STOMACH VOMITING BUG is my worst FEAR EVER! and well i'm scared :( because i'm going away to Sydney (i live in Melbourne) for a week with my dad and sister. and the thing is, i know sound soo weak and stupid, but i'm paranoid for some reason i'm going to get sick and vomit. it's stupid. and i won't have my mum! thats why im scared i dont like my dad, if i get sick and vomit, he'll be mad and tell me to get over it. and i have to share a bed with my sister! im also really scared that ill wake up and start vomiting for some reason. i know, it's so pathetic but im so worried i dont even want to go to sydney. i remember yr 7 camp, 7 nights, so scared i was going to vomit, i didnt! last year when we went to QLD scared yet again, BUT I DIDNT VOMIT. someone just give me reasurring answers! and how can i avoid this horrid bug when going away ^^