You think there is a vicious circle of anxiety over fears of a bowel issue and the bowel issue is from being anxious, correct? It seems that if you can stop worrying that something will go wrong then it won't, in which case the anxiety will stay away- and vice-versa, so if you can stop one the other might go away..
Try reading about these subjects to gain familiarity with keeping them under control or getting therapy if you have the money.