the metabolism slows down markedly around 2 weeks, its quite normal, it doesn't mean your reserves have run out (at your height and weight) it just stops showing on the scales every day from now on. try googling intestinal flora, digestive bacteria etc. it explains what causes the gurgling. we all have different strains of flora depending on diet and environment so their loss of daily fare causes more battles in some stomachs than others on a fast. it also helps the stomach stay calm if you avoid nerve upsets.
all the best
here's an interesting tidbit. not only can we now get our ancestral DNA read but also the ancestral DNA in our intestinal bacteria to determine which part of the world those ancestors migrated to and lived for many centuries. for people with chronic digestive problems it may one day help work out the correct carb/protein ratios one's gut flora is most comfortable with and/or how to gradually introduce a permanent new diet.