Have you had any checkups recently? It's a good idea to get regularly tested for Crohn's, especially if you are going med-free. It could be inflammation causing the symptoms, but if it isn't that then it could be a side-effect of the surgery - 15" is a fair amount to lose. Some people's intestines never completely recover from resection surgery. They are left with permanent loose stools or other IBS-type symptoms.
As for slowing the motility down, you can try Imodium, a soluble fibre supplement such as psyllium husk, or Questran.
Dx Crohn's in June 2000. (Yay )
Tried: 5-ASAs, azathioprine, 6MP, Remicade, methotrexate, Humira, diets.
1st surgery 20/2/13 - subtotal colectomy with end ileostomy.
2nd surgery 10/7/15 - ileorectal anastomosis. Stoma reversed and ileum connected to the rectum.
Current status: Chronic flare. Do I have any other kind?
Current meds: 50mg 6MP; Entyvio (started 3/11/16)