The last couple days ive had multi coloured stools, light brown orangish , yellowish and darkish green. should i be concerned? i do have ibs?

Stool color can be affected by diet. What have you been eating? Do you have associated pain? Gas/ bloating? Cramping? Persistent yellow or clay color is more concerning . Orange can be from escolar. F/u/ w/ MD https://www.mayoclinic.org/stool-color/expert-answers/faq-20058080

If you have persistent stool color other than the shades of brown, then you should be concerned. This changing color is probably combination of diet, medications and motility of gut. It does not look worrisome. Hope it helps.