I see this differently. Like SHE may think YOU are acting detached, so now SHE has. I mean think about it. You had a great date, you connected, you kissed. Afterwards, you showed interest by texting regularly and she was responding. Enthusiastically even. You made a second date, she accepted.
I dunno what happened but you came on this board having guys tell you to stop texting, stop acting interested, pull back, ignore her. WTF. Which you started doing and SHE stepped up. But then you continued along that path acting aloof, stopped initiating texts, cut texts short, wanting HER to chase you believing that is what she wanted, and would give her "vagina tingles." Even though her actions prior indicated she liked it when you were pursuing her and she was reciprocating. Not to mention, you don't know that you DIDN'T give her vagina tingles by acting interested and pursuing, you only had one date!!
Anyway, you broke the momentum dude. Your new aloof attitude is turning her off and you've noticed she’s detaching. Personally, I am not surprised. Not all women get off on chasing guys and guys who act aloof and disinterested. Maybe young insecure women do and if that’s what you want go for it. But good quality women, women worth having want a man to act interested and pursue her. LEAD. NOT act interested pursue her as you had been doing and then pull back, ignore her, stop texting, cut texts short and stop leading expecting her to chase/lead . That behavior is a BIG red flag for women.
Observe actions and how she responds to things you do and don’t do and PAY ATTENTION. To me, it’s very obvious what’s happening. Your new aloof attitude (following the advice here) has broken the momentum and she’s detaching.