Getting a shot TOMAROW?

ok, i despratly need help. i think i have an actual phobia of needles i mean im not scared of it hurting. im scared of the needle! i dont like the thought of it being in my skin. is there anything u can think of to get my mind off it? i am trying to not freak out this time im mean im wayyyy to old (14) and lasttime i didnt freak out untill they metioned "shot" then i started crying and shaking, and when it was done, it wasnt bad at all lol. so can u plz help me no tfreak out for my whooping cough shot tomarow?:)