Police say they arrested a Quincy man Easter Sunday on drunken driving charges after he drove into the parking lot of the Cohasset police station and urinated there. Police said Christopher Callinan, 31, wound up at the station after a woman called to say her car was being followed by an erratic driver, and police instructed her to drive to the police station. The other car followed and the driver got out, began to urinate next to his car, and was arrested after failing several field sobriety tests, police said. Callinan was held overnight at the station before being arraigned the next day in Quincy District Court, where he pleaded not guilty to numerous alcohol and driving-related charges, police said. “When alleged drunk drivers come right to us, we are glad to accommodate them with a place to stay for the night,” said acting Police Chief William Quigley.