Dont know whats wrong with my stomach

[shortie27]

Hi everyone,
I am a 27 year old female and have a problem with my stomach that is bugging me now for almost 2 years.
The problem is that I get severe diarrhea after or while I eat something.
In the beginning I thought I had a stomach bug but as I said I have this problem for almost 2 years now. Somtimes I cant even finish a meal, it seems as if the food is going straight through my system. The diarrhea is not there all the time, it seems to come in episodes and sometimes its stronger than other times.
First I though I have a food intolerance but like today I only had a plain soup and as soon as I finished it I had to go to the bathroom.
The diarrhea is always accompanied with painful cramps. Usually the diarrhea is watery, sometimes with mucous or blood.
Sometimes I dont have it for weeks and than all of a sudden it hits me again and it can last days.
It gets kinda scary because I am afraid to go and eat out cause I am always worried that I get diarrhea.
Everytime I have the diarrhea I am very tired and lethargic as well. Usually I lay down after a severe episode and I sleep for hours.
It really starts to bug me and I don't know what to do anymore. I am taking immodium like crazy and people look at me like I am crazy or so.
I went to my doc and told him but he didnt seem to be that worried. He took did some regular blood tests but appearantly everything is still within the limits..so I dont know.
Maybe anyone else has made the same experience and can give me some advise!

Thank you!!!