Hi and welcome to the site, though I wish you didn't have to be here. :)
There are issues during recovery for a lot of people where their gut just isn't normal, they have softer or more frequent BMs than normal for them, they don't tolerate certain foods, etc. In my daughter's case, her menstrual period definitely brought on IBS symptoms of cramping and looser stool. Sometimes, especially early on, it's hard to tell if it's another relapse, or just IBS.
Unfortunately, however, your risk of another relapse goes way up after the first relapse. The risk of the first relapse is around 20%, but after the first relapse, the risk of another relapse rises to around 65%.
As far as distinguishing a relapse from IBS - it's helpful to analyze your symptoms carefully. IBS in recovery tends to get better through the day or within a day or so, but relapses tend to progressively worsen. Try also to see if you have other symptoms that were present along with your active c diff infection that aren't usually part of IBS like fever, chills, extreme fatigue, etc.
If you do end up having another relapse, I would ask your doctor about Dificid. Dificid targets c diff more exclusively thus sparing your good gut bacteria that you need to keep c diff in check, and it has adverse effects on the c diff spores. A lot of people here have said Dificid was their ultimate cure. In my daughter's case, who relapsed twice on Flagyl and twice on Vanco, a Dificid taper cured her. That's another option for you - a longer course of Dificid with taper, to allow your gut more time to rebuild the good bacteria and prevent getting into a cycle of relapses.
Here's a paper you can refer to, if your doctor isn't familiar with Dificid or Dificid taper -
https://academic.oup.com/ofid/article/d ... r-PatientsSome doctors may want to try a Vancomycin taper first - that's what our ID doc wanted to do. But my daughter just wasn't responding very well to the Vanco during that treatment, so we pushed for Dificid. She saw an almost immediate firming up of her stool with Dificid, and she felt more normal when finishing the Dificid than she felt after either Flagyl or vanco.
Also, try to stick with a blander diet and avoid raw veggies and salad type foods for a while. Some people say dairy is difficult for them in early recovery. Everyone is different, but a bland, BRAT type diet seems helpful for a lot of people early on.
Good luck! I hope you're back to healthy fast.