James Q. Stevens, bursting into tears after telling a Fairfax County Circuit Court judge he was "out of my mind" when he took 10 people hostage at Lake Braddock Secondary School last November, pleaded guilty yesterday to three counts of abduction and one firearms charge in connection with the incident.

Prosecutors dropped seven other abduction charges and a second firearms count in return for Stevens' guilty pleas. As a result of the plea bargain, the maximum prison term that could be imposed on the 18-year-old is reduced from 104 to 32 years.

In a dramatic courtroom appearance punctuated by tearful, emotional outbursts, Stevens presented his first public account of his 21-hour takeover at the largest school in Northern Virginia. Stevens testified that the incident was a case of a teen-age romance that had soured and a "stupid, childish, immature" reaction on the day after his break-up with 17-year-old Rebecca Golas, a Lake Braddock student.

"I treated her like a queen; I loved her," Stevens said, eyes filling with tears. "I asked myself, 'What is wrong with me?' I was out of my mind."

The tiny courtroom in the Fairfax County Judicial Center was packed with friends and relatives, many of them weeping openly during Stevens' testimony. The day-long hearing was held to determine whether Judge Richard J. Jamborsky would accept Stevens' guilty pleas.

Stevens wept uncontrollably at one point, prompting Jamborsky to recess the proceedings. Stevens' former girlfriend, seated in the rear of the courtroom, also burst into tears as a bailiff led Stevens out of the courtroom.

Back on the witness stand minutes later, Stevens said he was desperate when he pulled his .22-caliber rifle from under the bed, tossed it in his car and drove to Lake Braddock shortly after noon Nov. 10.

"I did it as a last resort," he said. "I decided that even if I have to use force on her, I'll get her to talk to me. I took the gun, and I looked at it awhile, and I didn't care what happened to me."

Stevens said he momentarily contemplated suicide.

Instead, he quietly walked into the main hallway of Lake Braddock, the school he had attended the year before. As he walked down the hall, cradling the hunting rifle that had been a Christmas gift from his mother, Stevens recalled, "I was getting really nervous . . . I was shaken and scared."

When he darted into the school's administrative office, Stevens said he was startled by the response from office workers: "They started laughing. I couldn't understand why." That's when he said he fired the first shot, shattering a fluorescent ceiling light and sending the women in the office scrambling for cover.

Stevens said he never intended to take any hostages, but became caught by the situation and didn't know how to end the siege.

"They [police] had machine guns pointing at me down the hall," Stevens said adding. "I thought that if I let them go, the police were going to come in and shoot the place up and I'd be in there."

Stevens said he never intended to harm the hostages, though several school officials testified they were terrified at points in the takeover. No one was injured.

John G. Cockey, who was one of the first school officials on the scene after the first shot was fired, said Stevens threatened to "blow my brains out."

In the plea bargain agreement, Stevens was charged with the abduction of Cockey, who remained in the office only a few minutes before Stevens ordered him to leave; John W. Alwood, the school principal, and Arline Didier, who spent the 21 hours curled under a copying machine, unknown to Stevens.

He also was charged with using a firearm in the abduction of Alwood. That charge requires a two-year sentence; Stevens could be eligible for parole in under five months. Defense attorney Guy O. Farley said he does not expect Stevens to get a stiff sentence.