This is very odd because those do sound like pretty classic IBD symptoms. When you say low fever how low is low? And how does it compare to your temperature before your symptoms started?
Have you been taking any NSAID or PPI meds? (Which might
give a false positive faecal calprotectin result.)
No test is 100% perfect, so it is possible small spots of active inflammation could have been missed, you could have gone into spontaneous remission, you have microscopic inflammation (although biopsies should pick that up), or it really is 'just' IBS.
Long story short: I think you need more testing. I'm just not sure when. If you've just had a colonoscopy then you would probably be better off waiting 6-12 months before having another one. But if you really can't bear it, then carry on with trying to get a second opinion.
I'm assuming that throughout all of this the symptoms haven't changed? (Either for better or worse.)
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)