Forum:This is hard

wats up with this game its so hard i went thru the missions up til bone head and he kills me with like 4-5 shots every time... my sheild is wack against him and my weapons arnt affective at all... im level 7 and i use all me ammo tryin to kill one guy... wth... any sugestions, please dont be a smart azz i just got the game and could use some advice....