London Chemtrails?

Today was a lovely mild morning with clear skies. As I trotted to old st. tube station, I noticed streaks of white in the sky.  I decided to snap some shots of em with my silly iphone.  I almost immediately discarded the idea of them being jet streams, for there were a few odd things about them...  first off, there were about three, maybe four, that I could see.  the most prominent one had a very sharp cut off at the beginning and end of the streak, and there was no jet leaving from it, so why was it still lingering? I've seen plenty of jet streams before and they didn't look like this.  The second streak was just the same and probably parallel to the other.  in addition to those, I saw further in the distance a few more faint streaks in the sky crossing once, and then I saw three jets flying.
Even more, later in the day the once clear sky had turned into a huge overcast.  This could obviously be because of how the weather is here, but I have an itching feeling those streaks aren't just jet streams... here are the photos I took this morning and a brief excerpt of a documentary on chemtrails for your viewing pleasure.  educate yourself people! this stuff is serious- it is extremely harmful to the health of humans, animals, and MOTHER EARTH!!!!!!!