I have been having very strange bowel movements for the past few months. There are: prominent black streaks in the stool, about 7-18mm in length, at times a pinkish tint throughout the stool, usually with white/brown thin strings trailing off (around 8-14mm long and a couple mm wide). Sometimes there are also yellow balls around 6-12mm in diameter in the stool.
This is accompanied by a constant burning abdominal pain, in the centre of the lower abdomen, which gets worse first thing in the morning when I haven't eaten, as well as at night before bed (which I have suffered from for over 5 years).
I am vegetarian and consume at least 3 portions of fruit and vegetables every day, along with a substantial amount of soya protein.
I have suffered from diagnosed IBS-M for 3 years, and am a male in my early 20s. I'm quite worried about what this could be, so any help would be appreciated!
Here is the image (I cannot upload on the list directly, apologies): https://imageshack.us/i/pleMny4Zj