Overeating??

DS has always been a spitter, but it just seems to be getting worse and worse. I've gone through at least 8 cloth diapers cleaning up copious amounts of his spit in the past 5 hours. I have already stopped eating all dairy (due to his green stools and excessive gas), and I keep him fairly upright for a while after feedings. I try to burp him really well (which of course makes him spit), but then he'll be spitting up again before I know it. It rolls out when I change his diaper. It flies out when I pick him up to put him in the carseat. He burps when I wear him and it's oozing down my cleavage. Argh! The pain from his burps has even started keeping him awake. He can be sound asleep and then he'll start fussing. He has a particular cry that I have finally diagnosed as the "help! I have a bubble" cry, and he is inconsolable until we can get the burp out. This generally happens at least once a night but last night lasted from 8pm to after midnight. He is nearly 11 weeks old and still nurses for at least 20 minutes a session every 1.5 to 2 hours except for at night when he might give me a 3 or 4 hour stretch and generally just nurses for about 15 minutes. He's gaining weight really well (up 4 pounds from birth weight already), so I know this is technically just a laundry problem, but it's really quite frustrating. It is beginning to seem like he eats so much that he winds up throwing up a ton of it and then getting hungry faster. Could he perhaps be overeating? FWIW we've done two weighed feeds with an LC for other issues, and he took at least 4 oz both times. Since he gets at least 11-12 nursing sessions in per day, I'd estimate he's taking in b/n 30 and 44 ounces per day. Would it be at all wise to limit his nursing sessions to maybe 15 minutes? I'd love for him to space out his daytime feedings, but that doesn't seem to be happening yet. I'm really trying to follow his cues, but my mommy gut tells me something isn't quite right here.

Sorry for the long story. Summary: can breastfed babies eat too much??