It really depends on the type of anxiety.

First off, distract yourself from the anxious thoughts. This won't cure it obviously, but anxiety is a disorder that preys on your thoughts and makes you think in cycles that do not help. You should read a book or watch a movie or show, go out if you can etc.

Secondly, learn how to breathe properly. A lot of the 'panicky' symptoms come from hyperventilating when you are anxious. Here is a good explanation of it: http://www.anxietybc.com/sites/default/files/CalmBreathing.pdf

When it comes to googling symptoms, things can get a bit tricky. On one hand, if you have a particularly scary symptom and aren't sure if it's due to anxiety, googling it can help you figure out that it's 'just' anxiety and not something worse.

However, if you google symptoms and can't find them or they relate to other google searches of 'worse' diseases, then you can become more anxious. So generally, googling should be avoided.

Some websites can really help distinguish between other symptoms and anxiety symptoms and can help you overcome them. The 'Calm Clinic' is a great website that helps you through your thoughts and symptoms.

There are also many anxiety chat rooms that you can google (however, you should only use these when you are seriously anxious because overusing these sites can lead to over-thinking about your anxiety).

And last but not least, there is always CBT and mindfulness/meditation to help cope with the thoughts and try and change them. If you can't afford therapy, there are numerous tutorials and youtube videos online explaining CBT and demonstrating meditation etc. It is always better to see a professional but I understand that's not always easy.

Sorry for the long post and I hope anyone suffering from any mental illness can find some relief in it! Have a nice day :)