What could cause a loss of appetite, diarrhea, and other gastrointestinal symptoms after a light period?

Hi doctor,

I am a healthy 43-year-old woman. My height is 5 feet and 4 inches and, I weigh 135 lbs. I have been using Yaz birth control and Flonase nasal spray for over eight years. I had a DNC done 22 years back. I had a C-section and delivered a healthy baby boy 16 years ago. I had no complications during my pregnancy. A week ago, I had my period. I always have some menstrual issues due to which I have cramps and I used to feel irritated. I have to take Ibuprofen. I had light bleeding on the first day as compared to other months. The second day was even lighter and that day I lost my appetite too. I felt like I could not go through my normal activities for the day and told my husband to take me to the ER. They did a urine test (I was not pregnant), CBC, and a CT scan of the abdomen. Reports were negative and I was allowed to go home. I had no fever, no vomiting, and no nausea and I took rest after coming back from the hospital.

I felt a light tightening sensation in my abdomen and had no appetite (I could not even enjoy my morning coffee which I normally enjoy). Watery diarrhea also started, and I forced myself to eat. I took some Benadryl to help me sleep that night. I visited my doctor that day and she did a urine test and CBC which was negative. She said that I could be depressed which I strongly disagreed with. Yet I made an appointment with the psychologist. I did not have bowel movements that day. That day I also visited the gastrointestinal specialist. She said that the tenderness in my upper stomach and sudden loss of appetite was most likely due to a virus, but she suggested a HIDA scan and gave me Nexium to try. I forced myself to eat small meals that day. The next morning, I woke up and took a Nexium pill before breakfast. My appetite improved a little that day. I ate two slices of white cheese and spinach pizza for lunch. I also felt I had a little more energy that day and I had a firmer bowel movement.

For dinner, I ate only a bowl of chicken noodle soup, and I felt full. I had my HIDA scan done the next day. I did not take Nexium that day and I had no appetite that day also. The HIDA scan went well with no complications. So, I suffered from six days of no appetite, difficulty focusing, diarrhea with small pieces of feces, and little energy to do all my normal daily activities. Throughout all this, I drank lots of water and Gatorade to keep me hydrated. My doctor did not tell me to visit her again. I am assuming that there is nothing serious with my gallbladder. I have never experienced a sudden loss of appetite before. This one has lasted for six days so far. I have previously had the stomach bug, food poisoning, and the flu symptoms before, and I know what they feel like, but I have never felt the current symptoms previously. How long should I go with no appetite before I need to see my doctor again? I can also honestly tell that I am not depressed so these symptoms are due to another cause. Please help.

Thank you.