First time my female pit is giving birth? what should i know?

You should know how to contact your vet. It would take a while. Your vet is the answer. After this birth, be sure to spay so that your dog will not get pregnant anymore. Birth is a wonderful and natural thing, but only to those who have specific good intentions and know what they're doing. Just ask your vet what to do. Giver him or her a call. They will be your tool to guide you through this whole pregnancy. Listen to me...you cannot aid your dog in giving birth without a vet by your side or on the phone talking you through it. Please, trust me.