I am going to be very careful what I say here, because Gina Ford has a very litigious history with criticism on MN.
If a baby cries, and is comforted by breastfeeding, then basically they wanted one of three things: closeness with their caregiver; to suck (which they find very comforting) or they are hungry. Nursing works very well for all these needs, but there are reasons why it may not always be practical, particularly if you have older children. If the need is one of the first two, and you don't want to nurse, you can meet it in other ways - sling, cuddles, dummy, etc. If the need is hunger, they need milk.
A baby's tummy is tiny and they need everything that goes into it to be nutrient dense. If feeding them water works, surely it is only because it fills up their tummy with empty volume. Whilst it may be a good tip for a 12 or 18 month old who you are sure is not hungry (and may simply be thirsty), IMO it is not appropriate for a child so young.
I would recommend throwing away the book and enjoying your baby. It is absolute rubbish to suggest that most babies do not need a night feed by 16 weeks (a myth perpetuated by many baby books). Statistically I believe most children wake for a feed at least up to, and often well past, six months. Something like 50% of children wake regularly in the night until one (can't find the statistics, but I'm sure someone could).
You sound like you are doing brilliantly. Trust your instincts - you know that it seems wrong to deny him milk, and you know that your body doesn't want to. You and your baby are a unique relationship - don't let a book tell you how it should unfold.