Help breast milk

Doll • Premie baby born Feb 23. Due date April 15th. 🙏👶💙 Follow me on insta -ZULLYBRITO
So I pumped 4oz & only gave my baby 2oz in the bottle I still have 2 more oz for next feeding is it still good to feed it to him? 
It's before the 4 to 6hours before it get bad.