The musician was arrested on DWI charges on June 18 after a night out with friends at the American Hotel in Sag Harbor.

Justin Timberlake was very upset after his arrest on Tuesday.

The “Selfish” singer, 43, was taken into custody on DWI charges after spending an evening at the American Hotel in Sag Harbor. He was held overnight and awaited his arraignment on June 18.

“He was freaking out and stayed up all night when he was in custody,” a source tells PEOPLE. “He’s insisting he only had one drink and it wasn’t some wild night out.”

Timberlake’s attorney did not respond to PEOPLE’s request for comment.

As per the arrest report obtained by PEOPLE, Timberlake told the arresting officer, “I had one martini and I followed my friends home.”

On Thursday, a source informed PEOPLE that Timberlake’s tour would proceed as scheduled despite his arrest.

“It’s business as usual for him,” the source shared. “The tour is continuing as planned.”

Never miss a story — sign up for PEOPLE’s free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

The singer-songwriter was on a temporary break from his Forget Tomorrow World Tour when he was arrested earlier in the week.

He’s scheduled to perform in Chicago on June 21 and June 22, as well as in New York City on June 25 and June 26, with the tour continuing through December.

Timberlake was charged with one count of driving while intoxicated and received two citations — one for running a stop sign and another for failure to stay in his lane — after leaving the American Hotel on Tuesday morning. The arrest report also noted that Timberlake’s “eyes were bloodshot and glassy.”

Before being taken to Sag Harbor Police Headquarters, where he stayed overnight and was released the next morning, Timberlake refused multiple times to take a chemical test.

Timberlake’s court hearing is on July 26, the same day he’s scheduled to perform at the Tauron Arena in Kraków, Poland, for his tour.

“Mr. Burke looks forward to vigorously defending Mr. Timberlake against these allegations,” his attorney Edward Burke Jr. said in a statement to PEOPLE on Wednesday, June 19. “He will have a lot to say at the appropriate time. He is currently awaiting full discovery from the DA’s office.