Close Call with Huge Triangular Craft

I was driving home at approximately 2:30-3:00 a.m., heading north on I-5 from Everett to Arlington. It was a clear night. As I approached the Smokey Point Exit, I noticed a very bright white light (the size of a bright star) traveling from the east to west. It was several miles north of my location. At first, I thought it was a shooting star. But it wasn’t moving as quickly, and it was blinking at the rate of about once per second as it moved across the sky. I watched it for several seconds, and thought perhaps it was a satellite. As soon as that idea crossed my mind, the light suddenly shot back the way that it came, zipped up, zipped north, and then shot east again...and disappeared. It startled me quite badly, and I felt nervous as I continued off I-5 at the Smokey Point (#206) exit. I kept searching the sky, looking for the mysterious light, thinking it might reappear near the place that it had disappeared.
 As I turned east and came to stop at the light at Smokey Point Boulevard, I glanced around and looked directly up. I was terrified to see an extremely large triangular object hovering directly above the intersection. It was so low that the streetlights shined on its underside, highlighting large rectangular shaped panels and what appeared to be rivets that were spaced very far apart.  I can’t describe the size of the craft, because it extended beyond my scope of vision lengthwise, and I could see clusters of small white lights that indicated the shape. Could it be that they saw my headlights, and traveled to the intersection where I was heading toward? It HAD to be more than a coincidence.
 I couldn’t believe my eyes. I looked around for other people who might see what I was seeing, but there were no other cars around, and no people to be seen at the 7-11 store on the corner.  Even after all I’d witnessed, I really hoped that my imagination was playing tricks on me, so I looked up and expected that "it" would be gone. But, it was still there. 
I then noticed that it made no noise and created no turbulence in the air. I got SO frightened that I ran the red light, turning north onto Smokey Pt. Boulevard and drove as fast as I could all the way home.
I never heard any other reports of this.  It has bothered me ever since, and I am uncomfortable to this day about looking skyward.
Date may be approximate, although the witness does not indicate that fact.  PD