Worried...baby seems to be eating less.

r2b2007

Hi ladies. My LO is 13 wks. For the past few wks, it seems that he's been eating less. He used to take both breasts at every feeding, now he only does that about half the time. Also, sometimes he will only be on the 1 breast for 7 or 8 mins, then be done with ithe session completely. He will scream and cry if I try to give him the other one. He seems to be peeing and pooping normally and gaining wt appropriately, but still. When mh gives him his bm bottle at night, same thing, he only takes about 3-4 ounces and he' s done. I can assume that he takes about that amount from me when I nurse him, right?   My friends kids around the same age seem to be eating a lot more, although they are ff....

So, my question is, is it normal for a 13 wk old to only eat about 3 -4 ounces every 3 hrs or so? Sometimes he will even go longer. I kind of wish he would eat more so that he would sleep better/ longer stretches during the night. Does that all sound ok? Thank you!