My 10 and a half week old son is now on 5oz bottles, since I moved him up he has gone from feeding 3/4 hourly to 5/6 hourly and has only been having around 20oz in a 24 hour period. I am exclusively pumping so he is having only breast milk, and has now started sleeping from 2300-0800 straight through. He doesn't act hungry between bottles but has been teething in the last few days. He is growing well and has met all his centiles etc. Should I be worried? Or is he just adjusting to having more milk in 1 sitting?