Don't worry about it Lauraimes! I solved my issue, so this thread is free for others facing the same question as far as I'm concerned.

From what I've read, PTs are something that might take a few uses to "build up" in your hair again. If it still seems overconditioned, it just might be. My PT really helped my hair, but I feel like I could do another right now and still benefit from it. I'd rather creep up on the right balance than use too strong a PT, though.

It's also possible there's an ingredient in that one conditioner that your hair doesn't like. Want to give us a list? Since your hair is similar to mine (I seem to recall) I might spot something that I know my hair hates, for example. And Kathymack is soooo helpful! I'm glad she's on this thread.
I sort of blog
I'm mostly away doing field work through mid-May.

Hair: curlybob, fine, dense, low-po, big waves/ringlets (2C/3A)
Co-Wash: Nature's Gate Herbal Conditioner
RO: YTC Carrot, Aubrey Organics GPB
LI: BS Shea Soft Styling Cream (HG)
Styling: KCCC, Garnier P&C Gel
1xWeek: low-poo, gelatin PT or Joico K-Pak
Hair Likes: aloe, coconut oil, humidity, protein, long walks on the beach