Extremely strange sighting

Hey guys, I saw something extremely strange yesterday and I think it might interest you. Perhaps someone could also shed some light on what I saw, because I'm pretty confused.

I live in Montreal, Canada. I was driving down the highway, stuck in traffic, when I noticed a plane that looked like it had just taken off.

Now, I see planes all the time. Especially along the highway, as the main airport in the city is on the way to my girlfriend's house. I drive past the airport many times per week and seeing planes taking off and landing is pretty normal.

However, this was not, simply because the plane that appeared to have just taken off was on the OPPOSITE side of the highway from the airport. I pass the airport on my left side on the way to my girlfriend's house, but this plane was on my right side and several kilometres east from where the airport actually is.

To my luck, the traffic became stop and go right around this plane and I managed to get a good look at it. It was quite low to the ground, literally looked as if it had JUST taken off. It was only a few hundred feet in the air, I would estimate. It's hard to judge the height exactly but it was quite low, I'll leave it at that.

Now, besides the fact that this plane seemed to have taken off from nowhere, something was VERY strange about it.

It was not moving.

It was tilted upwards, as if it had just taken off, but it was not moving. Not at all. It was just hanging there, floating in mid-air and tilting upwards. I was stopped right next to it due to traffic and it was not moving AT ALL! In fact, I actually started to think that maybe it was a blimp that was disguised to look like a plane for some weird advertizing thing but I don't think so...It definately was a normal looking commercial airliner and it was not moving an inch.

Unfortunately the traffic forced me to move on and I couldn't really look back at the plane. I was trying to find it in my mirrors but it was impossible.

Then it got stranger.

I noticed, maybe about 2 kilometres later, what looked to be a black plane with a strange shape flying at high speed accross the highway diagonally and towards the first plane I saw. I first thought it was a commercial plane but the shape of the wings and the tail was different and the lights, which were on, were in a different position (sort of behind the wings, under the tail of the plane). I thought it was black but as it flew over me it looked more like it was dark gray. When it flew under me I also knew for sure it wasn't a commercial plane because it was moving too fast, the "hull" of the plane was thinner and longer looking than a commercial plane, and there were no engines under the wings, which were angled back more than a commercial airliner. It looked to me like some sort of military plane or something, but I really have no experience with these types of planes so I have no idea. I should also add it was flying low-ish...Or at least lower than normal for planes in the area (although I have seen commercial planes that low before since it is somewhat near the airport).

I also noticed that for the next 5 minutes or so, there was a loud roar coming from outside, which I assume was the engine noise from one of the planes. However I should add that I had picked up speed at that point and my car makes alot of wind noise when I drive fast, so it could have been a normal noise that I had gotten used to but only noticed again due to me being on more "high alert" for abnormal things.

Anyways, that's my sighting. I have no idea what it could have been. I know that commercial planes cannot just "hang" in midair like that but I'm absolutely positive that it was doing so, as I was stopped right next to it for a while. In retrospect I wish I had pulled over but I was late for a job and couldn't really spare the time. It's certainly been on my mind ever since though...

Any ideas?