breastfeeding help please!

Help! I've just started block feeding my 14 week old as after reading up I believe she's been suffering from gastrointestinal symptoms due to my oversupply/forceful let down/ perhaps over feeding by misinterpreting her and thinking she's always hungry. It was suggested I block feed so since yesterday I've been feeding on the same boob twice instead of swapping after every feed to try and help her get more hindmilk and improve her farts etc which wake her up. Although now she seems to be have green watery (and one explosive) poos! She didn't have these before (or not very often) so now I'm confused and think I may be doing it wrong when I thought it would get better. Should I persevere or go back to swapping boob at each feed and just try and space her feeds to no more than every 3 hours as I feel she's been snacking/comfort sucking (she doesn't use a pacifier