A week ago this morning, for eight explosive minutes in the dark hours before dawn, the Reagan administration tried to change the face of Libya.

But seven days later the face remains the same: Col. Muammar Qaddafi.

Last night he told a Yugoslav television crew, the first foreign reporters allowed to interview him, that "the struggle will continue" against the United States and "it will widen."

The Libyan leader's interview with a team from TV Sarajevo at the Libyan Foreign Ministry building here lasted only 11 minutes and was filled with much of the same rhetoric that has dominated the Libyan airwaves since the U.S. attacks on Tripoli and Benghazi.

His remarks, however, were nevertheless suggestive of his state of mind.

President Ronald Reagan, he said, is "Hitler number two." The attack that hit Qaddafi's home and offices was "unprecedented." The warplanes killed no terrorists, only women and children and old men, he said.

The Libyan leader told the reporters that his soldiers defended him but even they "didn't expect the angels would fight on our side" against the overwhelming American firepower.

"We overcame the fear," Qaddafi said. "We are not afraid."

Even though Qaddafi is still alive and still in Tripoli, the question pondered by many diplomats here is whether he has changed, or his government has shifted beneath him.

No clear answers have emerged, and almost as many theories have been proposed as there are embassies. Some western diplomats contend that the Army has gained the upper hand and its officers have warned Qaddafi that a further escalation of the crisis would bring the country disaster.

They note that the people of Tripoli, rather than standing by Qaddafi, tended to take to the roads to escape further raids. They put some credence, without offering any substantive proof, in reports that violent dissension arose in some barracks around the country soon after the strikes.

By this analysis, the relatively moderate tone of Qaddafi's remarks to the international press, and, more extensively, by his aides and information service, suggest he may be chastened and drawing in his horns.

But other diplomats contend, as one put it, that "nothing has changed except that the Libyans will be maybe a little more clever in avoiding links to terrorism."

"The United States has sown the seeds of dissent," said one European envoy, "but it will not bear fruit as long as Qaddafi is alive."

Other foreign analysts speculate that Qaddafi will have to mount some sort of major operation, military or more likely terrorist, to vindicate the attack.

Qaddafi and his number two man, Abdul Salaam Jalloud, have talked about the American "lack of morality" and "disrespect for human values" shown by the raids.

Some analysts read from this a threat that no measures, no means, will be excluded in a war that no longer has any pretense of adherence to rules in the Libyans' eyes.

As vicious as the use of clandestine terrorism is, in the context of Middle Eastern politics those who use it have always enjoyed certain benefits, as have, to some extent, even those governments in the region who are its object.

Terrorism often is used as a tool of statecraft by one Arab country against another because a blown-up airline office or an assassinated diplomat sends a political message infinitely more powerful than diplomatic notes, but infinitely less costly than open war.

Certain rules are observed, the most important one being to keep the operations "deniable," usually by working through third parties.

Even if both the attacker and attacked know who is basically responsible, deniability allows enough diplomatic room for them to sit down and talk with each other when the necessary moment comes.

But as Qaddafi must see things now, a direct U.S. attack on his home and headquarters has ruptured all the rules.

"There is no possibility to cooperate" with the United States, he told the Yugoslavs.

Meanwhile, as nights remain quiet, nerves have calmed and Tripoli appears as busy as ever. Traffic moves in the streets and at night lights are strung along the main boulevards as if there were a celebration. Offices and shops are open. If there is a certain sense that a storm remains on the horizon, if there is a certain edge on daily life, there is no suggestion of panic.

Two visits to the airport yesterday revealed no signs of a mass exodus by foreign workers, but clearly many of them are anxious.

Gary Lawson, a Canadian geologist with the Oasis Petroleum Co. here, said this morning that he was thinking seriously about a call by Canada's Foreign Minister Joseph P. Clark for its 1,500 nationals to get exit visas and prepare to leave during this period of relative calm.

In sentiments common to many foreign workers, probably including the several hundred Americans now keeping low profiles here, Lawson said, "A lot of us are seriously considering the possibility of going if we have to.

"The reality of a raid is pretty shocking, and we witnessed quite a bit of it," Lawson said. "Before that we sort of treated it all in an offhand kind of manner; have our parties, go to the beaches and continue working as normal.

"But now that that's happened," Lawson said, referring to the air strikes, "and we've seen the force of what a bomb can do and the possibility of planes or missiles going a bit astray and landing on us in areas that aren't necessarily targets, it's a bit frightening.

"A lot of us are undecided," said Lawson. "A lot of us are glad our families are out."