There is a girl at school who I'm unsure of. Any tips?

I suck at having a close relationships with girls (I'm a boy). I've had many 1/2 chances at having a girlfriend, and I've stuffed up everyone as I have became too shy for some unknown reason. Around 3 months ago, I caught a girl staring at me a couple of times and was compelled by her. I talked to her a bit, and say the occasional hello while ping in the corridors. Unfortunately, I've ped her a couple of times during the last week or so and have looked up to say hi only to find she is off in her own world wondering god-knows-what. Have I left any chance I had with this relationship too late? Or does it seem like there may be some minute chance left? Thanks in advance.