When I entered the end I instantly died

When I entered the end I was almost instantaneously killed by fall damage (pretty much when i was loaded in I was dead )  . I have been to the end 100's of times and when I went back to see what happened nothing was out of place and I didn't die either . So I pretty much lost everything because of a glitch . It happened for a second time , from what I could figure out its the first time I enter the end when re loading in , but when I go back for a second time I'm fine