Sorry to post yet another question, but this is all very new to me 
I've been breast feeding twins for almost a month, and expressing 2 - 4 oz once or twice a day in addition (so that DH can feed in the evening if I get too exhausted - probably 2 or three feeds per week).
This has been going fairly well, but yesterday I felt much more engorged than normal. Then from early afternoon yesterday, DTS started producing green-ish poo, and tonight (3am feed), DTD brought up what looked to be a large proportion of her feed quite violently (I would describe it as projectile rather than just coming out of the side of her mouth IYKWIM). At the 3am feed they both seemed to struggle to keep up with the flow (guzzling).
From looking on the internet, green-ish poo can be a sign of getting too much foremilk and not enough hindmilk, which would tally with the engorgement and guzzling. It also seems likely to me that guzzling could cause DTD to bring back her feed.
How can I settle things down? I'd like to keep the expressed feeds if at all possible as it reasures me to know there are supplies in the fridge for those times when I really need to sleep. I thought about expressing some milk off before a feed to try and reduce the flow, but won't this just stimulate my supply even more? I don't know what to do!
Any advice would be gratefully received