Lua death Rune

[SpiderOT]

hello all
can anyone fix this script? it is about a rune like sd but finite rune (in action not spell) everything work fine but if i hit someone1 the damage go to me
simple i hit myself xD
here is the script

function onUse(cid, item, frompos, item2, topos)
storevalue = 1000
exhaustion = 1
smallruneid = 2307
lv = getPlayerLevel(cid)
ex = -(lv*1000)
    if (item.itemid == smallruneid) then
	    exhast = exhaust(cid, storevalue, exhaustion)
        if (exhast == 0) then
        doPlayerSendCancel(cid, "You are exhausted.")
		doPlayerSendTextMessage(cid, MESSAGE_INFO_DESCR, "You are exhausted.")
        else
        if (item.type > 1) then
		doSendMagicEffect(getPlayerPosition(cid), 29)
        doChangeTypeItem(item.uid, item.type-1)
		doTargetCombatHealth(0, cid, COMBAT_PHYSICALDAMAGE, ex, ex, CONST_ME_NONE)
		doCreatureSay(cid, "Death Coming!", TALKTYPE_ORANGE_1)
        else
		doSendMagicEffect(getPlayerPosition(cid), 29)
		doCreatureSay(cid, "Death Coming", TALKTYPE_ORANGE_1)
        doRemoveItem(item.uid, 1)
	    doTargetCombatHealth(0, cid, COMBAT_PHYSICALDAMAGE, ex, ex, CONST_ME_NONE)
        end
        end
    end
end
function exhaust(cid, storevalue, exhausttime)
    newExhaust = os.time()
    oldExhaust = getPlayerStorageValue(cid, storevalue)
    if (oldExhaust == nil or oldExhaust < 0) then
        oldExhaust = 0
    end
    if (exhausttime == nil or exhausttime < 0) then
        exhausttime = 1
    end
    diffTime = os.difftime(newExhaust, oldExhaust)
    if (diffTime >= exhausttime or diffTime < 0) then
        setPlayerStorageValue(cid, storevalue, newExhaust) 
        return 1
    else
        return 0
    end
end

i think the problem in

doTargetCombatHealth(0, cid, COMBAT_PHYSICALDAMAGE, ex, ex, CONST_ME_NONE)

 

[HamTheKratos]

i need that too