Self Diagnosis

The other day I had an interesting patient. She was very forthcoming about her symptoms.This is what she said
' From yesterday morning my Spondylosis began troubling me.It started at the base of the neck and then spread up to all nerves in my brain.From evening onwards it was my Sinusitis with unbearable pain around my eyes. Today morning I was better as I slept with out a pillow. But by afternoon because of my new glasses [ which I began using one month ago] I had dimness of vision and watering of eyes. As I felt bad I took a pain killer which produced 'Gas' in my stomach and I had to vomit.
Many patients describe their illness like that.They will have all the diagnosis ready.They are so sure of the reason for their illness that sometimes I feel why they had come to me.May be just to confirm the diagnosis? Or to show off their medical knowledge?
With such patients it is very difficult to get a true account of his/her symptoms.A patient should try to tell the doctor what symptoms he/she felt, the order of occurrence of symptoms[chronology],what triggered/aggravated and what relieved the symptoms etc.It is better not to tell what he/she think is the cause of the illness unless asked to by the doctor.Let the doctor reach his/her own conclusion.
If the patient already come with a diagnosis of his own,there is a strong tendency among doctors to come to the same conclusion which many a time may be incorrect.Especially it happens with less experienced doctors working in Emergency Department. Several times I had seen the diagnosis given by the patient written down in the case sheet from the emergency department overlooking glaring clinical evidence to the contrary.This sometimes result in delay in diagnosis and unnecessary medications.
Ideally the above described patient should have told me about her symptoms like this.
'Yesterday morning I felt pain on the lower part of back of neck which slowly spread up to my forehead.By evening that pain was less but I had severe pain around my eyes.Today morning i felt better,I don't know why.But by afternoon I had some dimness of vision and my eyes started watering along with headache.I took a painkiller but after some minutes I vomited'.
However smart you are, it is always better to leave to the doctor the job of finding the cause of your illness.