I would guess that yes, those two things moving away from it would be it's rockets disengaging. But ya, what the hell was that that passed by on the top right. It was moving pretty quick.
If it was filmed in infrared, and the object wouldn't have been seen any other way, sure, it's the ACTUAL definition of UFO. It is unidentified and it's in space, so that's considered flying, and it must be an object, we can see it, so yes, UFO.
But, that doesn't mean it was an alien craft. It may well have been, but not necessarily, that's all.