7week old drinking 4oz every 2hrs is this normal?

[mummytasha18]

My lb was drinking 4oz every 3-4 hrs but when he got 6weeks old he started only lasting 2hrs between feeds I assumed he was having a growth spurt but he is still drinking the same at 7weeks! I've tried upping his oz to 5 but he will still leave an oz. I was just wandering is this okay and that I'm not over feeding him! Tia! X