Here is one of the dumbest replies.
The NHS dont want to you go to your doctors as a first point of call anymore, as they prefer you to ask nurses, or use other resources such as pharmacists. This is to free up their time to treat those that really need it.
So why not apply the above to pets and vets. This site will have a wealth of people that have looked after cats as pets for years and years and been through similiar. If all your answers point towards a vet visit great, you know then, if you get a lot saying try this or that then thats a result to, that may have saved the ditress of a vets visit, time and expense!