Does this sound like IBS

So, for about 3 years now, i (M 42) have been suffering with tenesmus on a pretty regular basis, particularly on a night.

About a year ago, I noticed blood when I went to the toilet so went to the GP. They asked me to do a FIT test, which came back "negative" and basically discharged me. A few months back, the tenesmus was getting worse si I went back to the GP, who did another FIT test and some bloods and said everything looked fine and that I have IBS.l and to try a low FODMAP diet.

I've been trying the low fodmap diet but haven't really noticed any improvement, in fact things seem to be worse in that I am now alternating between constipation and diarrhea, as well as having foul smelling flatulence. I also think I noticed blood in my stool again today.

I just wondered whether these symptoms seem consistent with IBS as it just feels like a catch all diagnosis.