First diarrhea then nausea then constipation, now soreness and bloating.......what could it be? been over 3 week period

Start with diet: The first thing to do is examine your diet and see if your eating habits have changed over the past few weeks. The next thing is to add extra fiber to your diet. If that doesn't get you moving, try MiraLAX (polyethylene glycol) or some similar remedy. If that doesn't get you going right away, see your doc.

Many Possibilities: By symptoms you describe: altered intestinal function, be related to emotional, nutritional, hydration, local blood flow, reaction to changes/activity of intestinal flora (bacteria), etc. Physicians do not have all the answers; physicians are trained about aspects of body anatomy, physiology & promote detective work (from history up to expensive tests) looking for clues in the hope of benefit.