Are you sure that they are looking at you like that? I think that social anxiety and being overly vary about how people perceive can make you interpret things into peoples looks and behavior that aren't there.
I don't know if that's the case, but just putting it out there. I used to think that people were looking at me in a negative way and that strangers hated me. I still think it's really unpleasant to pass cars that are driving past me because I think that they are looking at me.
Anyway, what I do know is that people are sometimes staring at me because I am a very tall woman. Especially short men have problems with that, but they aren't always just staring. They also feel the need to comment on it.
Usually I just avoid looking at people if I'm passing by them when I'm walking somewhere.