Highly unlikely your stomach was eating itself, even at 55 days. Having said that, there are good reasons why the Scriptural pattern is 40 days of fasting. Our Creator knows our bodies better than we do, and anything over 40 days carries known risks.
For this reason, anything over 40 days should only be undertaken while under medical supervision by a qualified professional who understands the physiology of fasting.
Most medics are clueless, and would throw up their hands in horror at the mere suggestion of any fasting, nevermind one as long as yours.