I think short people make "my kind of short" feel tall! :D! I'm only taller by a few inches and I have an aunt who is a bit shorter than you and she makes me feel like a GIANT!! I love it! :D! with everyone else i feel midgetized! lol :/
Anyway, I don't know what you're referring to when you ask if you're too short... too short for what? To have a boyfriend? That depends on the guy... You're too short to date a guy who is not attracted to short girls but you're NOT too short to date a guy who IS attracted to short girls.
In general, yes you are short, I think average size would be considered 5'4" - 5'7" for a girl.. anything over is "tall" and anything under is "short"... Short is not that bad... I bet some midgets wished they were "short instead of "midgets"... Nothing against them.. just making a point that some people view your height as something awesome! and wish for it.
I'm 4' 10" and in the middle weight range like you. I always wish I was taller so I could have long elegant legs. But it hasn't seemed to matter... occasionally I get guys hating on my height, but I get hit on pretty often so I don't think most guys mind :)