Brief Answer:
Most likely irritable bowel.

Detailed Answer:
Hi,
Initially i would would like to thank you for choosing this platform to ask your query,

As per the brief history given by you most likely you are suffering from irritable bowel disease.
Irritable bowel syndrome is a disorder of the large intestine. It may cause abdominal pain, bloating, diarrhea and constipation. The condition is not life threatening in nature and does not make you susceptible to colon disorders such as Crohn's disease, ulcerative colitis and colon cancer, however, symptoms of IBS may act as deterrents in leading a normal life.

Most common symptoms are-
You may experience symptoms of constipation or loose motions.
Very Frequent episodes of bowel.
Abdominal cramps especially on the lower part of the abdomen
Constant bloating
Abnormal stool structure
However its not necessary that all symptoms are present in every patient.

Initially few tests are recommended as IBS is a diagnosis of exclusion.
Tests are
Upper G.I endoscopy
Colonoscopy(to rule out inflammatory bowel disease).
Once cleared treatment can be started on guidelines of IBS.

-Different procedures are used to treat IBS, which vary from person to person. However, one single treatment does not work with everyone.

Lifestyle and Dietary changes:

By making several basic modifications to your regular diet and activities, IBS improves with time. Here are some tips:

Avoid caffeine in any form such as coffee, tea or soda.
Increase the amount of fiber in your diet and include vegetables, fruits, whole grains and nuts.
Drink three to four glasses of water regularly.
Smoking should be abstained from.
You must undertake relaxation techniques and work out in order to reduce stress.
Dairy product consumption must be reduced.
Try to eat frequent, small meals instead of fewer large meals.

Keep a record of the types of food you consume so that you can identify the IBS triggering food items.
Try to eliminate high gas producing food items from your diet. Food items which may result in passing excess amount of gas such as carbonated vegetables and vegetables such as cabbage, broccoli and cauliflower should not be consumed.

Take Metamucil 2tsf once daily before going to sleep.
Take a good quality probiotic like Econorm three times a day for atleast a month.

Medications that can be discussed with your cardiologist are-
-Antispasmodics are used to control muscle spasms in the large intestine.
-Antidiarrhoeal medicines are used to control the symptoms of diarrhoea.
-Antidepressants are also used in case of some patients with IBS for relief.

For any further professional opinion follow up with advice.

Thanks

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