Talk to General Physician on Burning Stool

Hi I am having burning stool since two days. My nuerologist gave me magnesium citrate two days ago for muscle relaxation which is also helping me a lot with my constipation.. can the burning stool be because of this supplement? Because I haven’t been eating anything spicy or oily. I had piles two weeks ago but now there are two teeny balls and no pain during or after passing stool so I doubt the burning stool is because of that. I touched the anal area too but there was no pain there. My doctor gave me hadensa cream I want to know if I can apply that occasionally if I feel that there is burning or pain because of constipation but pls tell me what’s the reason for burning stool. I am taking risek and colofac three times for ibs since a month which is under control and I am doing much better now in terms of ibs.