It sounds like irritable bowel syndrome, which I was going to say until I already read that you were diagnosed with that. One thing I know about IBS because one of my friends on here has it so I looked into it a bit, is that you are more likely to have anxiety because of it. I know that if I'm super anxious, I need to go to the bathroom, though I don't actually need to go, and just super anxious. There just seems to be a lot of stress right now in your life also. If you feel this anxiety/depression is affecting your life a lot, I suggest you find a mental health professional to figure out if that is something that may be affecting you. I wish you luck on your journey of life .