Problem is, even if there was, they couldn't diagnose something from a post. There's a reason doctors have you come to them. They need to take a look at the area themselves.
You take almost any symptom a person could have, and there are likely dozens of explanations for it. Only through testing can these be narrowed down.
A random pain in the chest, for example, could be anything from gas (just a burp) to a deadly heart attack, with a lot of less extreme possibilities between. There are very wide ranges for these things.