I have been dealing with Anxiety for the last 15 or so years, and there are certain things I did to control my anxiety (either stopping it altogether, or bringing it down to a level that is manageable). And I haven't had a panic attack for years, or ever since I first started changing the way I live. I am also not on any medication.
First and foremost, stay 100% away from caffeine and other stimulants (red bull, Ephedrine, etc). If you can't, get used to your anxiety. I think being a little bit more tired during the day is an acceptable side effect.
This means no coffee, tea (no decaf, Herbal are alright (chamomile is great)), pop (pepsi, coke, rootbeer, Mellow Yellow, etc), chocolate, decaf (still has a bit of caffeine), etc. Staying away from all types of pop is a good idea, because your body may also be extra sensitive to refined sugars (pop, junk food, white bread (refined bleached wheat), etc).
Also booze/drugs of any kind will make your anxiety worse, as it is a depressant.
Avoiding stimulants will automatically bring down your level of anxiety to possibly a level that you can live with and control. You might notice that it is still there, or showing the top of its ugly head, but it does not set you off, or shut you down the way the way combining a stimulant with anxiety usually would.
Secondly, hit the gym or get exercise as much as possible. This will help you blow off stream, and increase the amount of good chemicals in your body, that ultimately increase your mood for the better. Also Yoga and meditation can really help (stretching, breathing, relation, etc).
Thirdly, don't worry about what you "can't control." I found I was worrying about everything, and I learnt to let go, or recognize when I was getting anxious, and stop it, but focusing on something else. Or taking a deep breath.
If something you can control is at the base of all your problems/anxiety, them do something about it. It might be your job, or relationships (spouse, bf/gf, family), etc. You have the power to change these types of situations.
Also, take the time to smell the roses, and get out of the rat race as often as possible. This will give your body a chance to relax and realize what is most important. Life is short, enjoy it!
If you were to implement all of the above to their maximum for a couple weeks to a month, you should 100% see a major difference. And after being off stimulants (booze, coffee, etc), you will be able to identify the increase in anxiety pretty easily should you go back to them (the affect of one cup of coffee can last several days).
There are also a number of supplements on the market that can naturally help anxiety and depression. Keep in mind that all products are not created equal, so you might need to try a different brand or two, until you find what you are looking for. Also keep in mind that some vitamins are water soluble and others fat soluble (fat soluble can create toxicity if you consume too much).
I've had the most success with 5-HTP (25 - 50mg per day) (which is a pre-curser to serotonin (controls sleep, mood, etc)), when combined with a B-complex vitamin (usually 25 - 50mg per day). But since I am not a doctor, please speak with you health professional before implementing any new program, or supplement.
I really hope this helps, and I am 100% sure if you were only to exercise, eat properly (whole foods such as veggies, fruits, whole grains, etc) and avoid stimulants, that you will feel much better in no time flat. Also don't forget to remove all negative situations from your life.