Nipple Rasa Sakit

im 29w6days pregnant now . im just wondering people said supposed to be air susu dah mula keluar but mine only sakit bahagian nipple tapi tak ade air susu kluar lagi . its there anyone yg perna rasa mcm ni? cause this is my first baby actually , sbab bila tnya dngn doctor drg ckp normal , mak dngn kakk pn ckp normal . ada tak yg perna mcm sya? nak tnya bila air susu akan kluar?