The general idea here is not fully correct in my opinion.
I once got a girl's number. Texted and asked her out, she did not reply, so I went no contact.
Almost six months later, she texted me: hey, how are you doing?
me: good thanks, and you?
her: (no response)
Some weeks later she texted me again:
her: hello Pyros, are you still going to X club?
me: yeah, btw, tell me your FB so I can add you there
her: (no response)
Some months later she texted me again:
her: hello Pyros, what are you doing lately?
me: Im doing X and Y
her: nice, Im stying a lot blah blah
me: wanna grab a drink tomorrow night?
her: oh cool, ok
Then we met, I kind of figured out that she had an on and off boyfriend, but we made out, and ****ed in my car.
Some days later we ****ed again at my place, and I never called her again, neither did she.
So my point is, it does not matter if you nexted her, if SHE contacts you she still has some interest and if SHE decides, suddenly, that she wants to **** you, she will, so just be nice and cool when she contacts you because you never know.
You're too worried about: what if I showed her too much interest and she just wanted and ego boost?
So what? dont take it personally and just think she is a crazy *****, no big deal.
P.S.
I currently have some other girls I nexted because they did not show much interest, but I am waiting for some of them to contact me in the near future when 'they have their mind clear', in other words: she has no more boyfriend, no **** buddie around, she is not sad, she is bored, she needs some sex... among other reasons.