Basically, I just vomitted after drinking too much from a well and got sick. According to http://dayzdb.com/guide/11-standalone-status-effects vomiting does the following status effects:
-600 Energy (minimum of 100)
After vomiting, my character was hungry, so I ate a little bit more. I ate too much and started vomiting again. Now my character was thirsty, but still "completely full". After drinking a little bit, he vomitted a third time. Now he was feeling hungry AND thirsty, but his stomach was still full, so I couldn't eat and drink anymore without throwing up again.
Shouldn't it remove 1600 from your stomach if you loose 600 energy and 1000 water?