AN 18-YEAR-OLD Yeppoon woman broke into her former boyfriend's house, smashed walls and doors with a hammer before going after him with the weapon.

Brittany Lee Finn pleaded guilty on Monday in the Rockhampton Magistrates Court to charges in relation to Sunday night's offences.

Police prosecutor Clancy Fox said the victim had contacted Finn earlier that day to advise her he had found her bank card at his house. He said Finn gained entry to his house at 11.30pm via a window in the garage and smashed doors and walls with a hammer before being approached by the victim.

The court heard Finn struck the victim on the back with the handle end of the hammer and he then attempted to restrain her.

They struggled until they were outside and she was lying on the stairs when she pushed him in the face and into the garage door. Mr Fox said the victim then sat on Finn until the police arrived.

Finn was remanded in custody after Magistrate Jeff Clarke adjourned the matter until today while he checked on relevant sentences for entering a dwelling and attacking a person with a hammer.