But, yes. There are some online screening tests avaiable. Here is a Canadian screening test that covers symptoms of anxiety and depression. One option is to get a print of the test result to discuss the results with your doctor!
The webpage offers additional tools (anxiety diary) and even a 12-step cognitive-behavioral therapy program for anxiety disorders.
The Hamilton Anxiety Scale is often used by clinicians to evaluate the severity of anxiety symptoms. There is an online version provided by the Anxiety Community