I take it you posted here and nobody gave any suggestions?
Their are too many variables to do what you say. It is possible but garbage
in means garbage out. You have to supply a specific medical term and
depending on how common the symptom is then the list may be endless and
meaningless. The more valid data entry points that are put in the better the
results will be coming out.
Typing in heartache and getting a list containing common headache to Ebola
virus doesn't help.
In reality the way to diagnose is based on the medical history something of
which would be hard to enter in a computer and evaluate and the signs,
symptoms followed by a physical exam.
You need to have a trained observer to note signs and the proper medical
term used to denote symptoms.
The only reliable thing to do is see a professional.

Here's something, but it's probably not as extensive as you want:
http://familydoctor.org/symptom.xml

Frank,

Post your symptoms.    The others are right in that there are too many
variables    But Crohns illness and UC have many weird symptoms ,  and are
sometimes confusing even to the doctors.
Maybe something will hit a bell.      Do you have medical books.   Sometimes
if you can guess what it could be, you could look it up in the book.    I
believe Crohns is not caused by a medical problem, but if it appears (from
outside forces) it requires medical treatment unless the cause is known,
which I would describe to you, if it might be appropriate.
Gal