Thanks for your question on Healthcare Magic.
I can understand your concern. 
By your history and description, possibility of 
irritable bowel syndrome (IBS) is more likely.
Most common cause for IBS is 
stress and 
anxiety. 
So we should first treat stress and anxiety to improve IBS. 
So 
consult psychiatrist and get done 
counselling sessions. 
Try to identify stressor in your life and start working on its solution. 
You will need anxiolytic drugs too. 
Don't worry, you will be alright with all these. 
Drink plenty of fluids orally, eat high fiber diet like vegetables, fruits etc. Avoid junk food like pizza. 
Avoid stress and tension, be relax and calm. 
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.