I'm afraid of ! (basket, soccer , ALL sorts of etc)?

i know some of you might laugh after reading this question but it's not funny for me :( whenever any ball is whizzing past i'd react to that - like i'll jump or something and someone will just notice it and giggle. it's an embarrment! i don't know it's like some phobia! i've tried practicing by asking my sibling to throw at me and stuff i'd catch it without blinking and reacting so dramatically - but only for 2 seconds. I'M ABOUT TO HAVE P.E LESSONS ASAP and i feel like ditching them :/ unfortunately i can't because the attendance would count! Perhaps i think that it might hit me and my head would crack open or i'll get a bruise and the pain would overtake me! i'm as scared as ever and this phobia is not going away! :( and on top of that, i'm a clumsy person - HELP ME!