I gave up my breastfeeding pillow at 10 days, it was not needed once I stopped tandem feeding so I'm not probably a bias source of information on that But if you are finding it a hindrance then give it up for a week and see if you can cope without it. Especially if you start trying to feed one at a time you'll probably find a normal pillow will be easier as it is less bulky and annoying during a feed.

If you decide to buy a book to help please stay away from Tizzie Hall. She hadn't any children when she wrote that book and now that she does, even she doesn't use her methods. Pinky McKay has some lovely books on helping children to sleep which are much kinder to both you and your twins.