"I need help," Aljarrau Simmons-Waterhouse told police after attempting to harm himself and slapping his partner following a dispute.
Simmons-Waterhouse was at his Whanganui address on August 22 when his partner went to a nearby dairy at 8am to buy him a pie and something to drink.
When she arrived back, Simmons-Waterhouse was not happy with the drink she had chosen, so she returned to the dairy and purchased another.
In Whanganui District Court on Tuesday, police prosecutor Stephen Butler said Simmons-Waterhouse was also unhappy with the second drink and became agitated.
"The victim attempted to stop the defendant from harming himself," Butler said.