Chrisca, maybe I've mentioned this before but looking at your signature I am amazed by the similarities of our stories. Here's mine, a little different but still..false neg colonoscopy, age 48, rectal cancer diagnosis, age 53, large tumor 2 cm from anal verge, stage 3B, same treatment, and then the surgery for adhesions in 2013 (mine was open, though).
I did do the pelvic floor PT, it didn't improve bowel function for me but it did help with pain. It is worth a try and I have heard of some success stories so hopefully you will fall in that category. It seems those of us who had the low tumors with total rectum removal have the most challenges with bowel functioning. I ended up becoming an enema user, not everyone's cup of tea but works for me.
Good luck on your therapy, hope to read of good results!
RC 3B 7/2011 @ 53
Chemoradiation 5 weeks 8/11
pCR, 0/23 nodes
Folfox 1/12, Xeloda 2/12 to 5/12
SBO,lysis of adhesions 12/12
NED 11/12, 11/13, 6/16