Autohotkey execute scripts

i am trying to execute scripts by using shortcuts but cant do it. When i press shift, code is not waiting for other key and executing first condition. Can you help?

my code looks like that:

x := 500
~Shift::
sleep, 500
loop,
{
if GetKeyState("S","p")
    {
    Send, {BS}
    Sleep, 200 ; for buffer (1000 = 1second)
    Send, 600.01.02.02
    Send, {Ctrl Down}
    Send, {Enter}
    Send, {Ctrl Up}
    Return
 }
if GetKeyState("M","p")
    {
    Send, {BS}
    Sleep, 200 ; for buffer (1000 = 1second)
    Send, 600.01.05.02
    Send, {Ctrl Down}
    Send, {Enter}
    Send, {Ctrl Up}
    Return
 }
}
return