Clement grabbed her by the throat and began squeezing to the point she had "trouble breathing", Mr Wilson said.
He then pushed her on to the bed but she ran outside with her cellphone before falling down on to the driveway, the court heard. Clement then grabbed her phone and threw it against a fence, smashing it, Mr Wilson said.
"He kicked her two times to the side."
When police arrived, Clement was standing inside holding his toddler son, the prosecutor said.
"He held his 2-year-old son by the glass to stop police breaking in. He continued to resist."
When spoken to by police, Clement said "he just lost it".
Defence lawyer Peter Stevens said his client had been under stress because of the long hours he was working.
Judge Walsh said it was clear Clement had issues which needed addressing.
He remanded Clement on bail for a pre-sentence report including a home detention and community detention report to assist the court at sentencing on July 25.
A condition of his bail is not to offer violence to or threaten his partner.