Yeah i second that check mate kid. Giving too much attention can be a bad thing at first. It's better to give them just enough of your attention to get them interested, and then leave them wanting more. The more ways you can get the girl thinking about you, about being with you, the better.
I wouldn't advise to stop getting interested whatsoever, i'd advise asking yourself what is it that is different about the way you act around those you like/want and those you don't. Then you'll be better prepared.