StarGazer: I would say to play it by ear. It's possible to come back from that, but I wouldn't try too hard to approach her again. If a situation comes up where it makes sense to talk to her, then go for it. But it'd be a waste to try for her number again right away - it'd be you chasing after that prize some more.
Instead of approaching her and asking for her number again, make her work for your affection. That might take two or three conversations before she finally sees you as the prize again. Just remember to keep it light and fun with her until she does earn your affection back.
And do yourself a favor - approach other girls in the meantime.