It sounds like you may be suffering from anxiety attacks that turn into panic attacks.
An anxiety attack is when something bad happens to you or you’re thinking about something bad and you get really anxious. You can get so anxious that you might even have some physical symptoms. For example, you might get shaky, your heart might race, or you might get short of breath. An anxiety attack can last anywhere from a few minutes to a few days. The main feature of an anxiety attack is that you are worrying about something in your LIFE (for example, relationships, work, school, money).
A panic attack on the other hand comes on all of a sudden, out of the blue for no reason at all, and it’s all about your BODY or your MIND. You suddenly feel like you must be having a heart attack (or a stroke, or passing out, or choking, or vomiting, or going crazy, or losing all control) because your heart is racing, you’re short of breath, you may have nausea or tightness in your throat, and you’re shaking. A panic attack comes on within ten minutes, but can last anywhere from a few minutes to a few hours. The main feature of a panic attack is that you are worrying about your BODY or your MIND right then and there, rather than worrying about something in your life. Most people with panic attacks have gone to an emergency room at least once to make sure nothing physical was going on.
Some people actually have anxiety attacks that turn into panic attacks. For example, they will start to worry about something stressful in their lives, but then once they get worked up enough, they will start to worry about what’s going on in their bodies or their minds instead. (source: selfgrowth.com)
Things to do:
1. Remind yourself repeatedly until you can really believe that your panic attack is a natural - emergency response and you will not turn in to a shaky, flaky weakling who is about to pass out any minute. Your whole system is in high gear. You are actually stronger, faster, and quicker. Believe it.
2. Constantly repeat to yourself that panic symptoms no doubt are unpleasant, but they are not dangerous.
3. Know that just as you have a natural emergency response, so you have a natural "calming response." Yes, you can learn to calm yourself out of a panic attack.
4. Unpleasant symptoms of an anxiety/panic attack can be brought into control in just five minutes if you start calming down and do not pump more adrenaline in your blood by "panicking" about the panic attack.
5. Do not "fight" with the symptoms of a panic attack. Try to "flow" with the symptoms and allow yourself to become calm.
6. Learn a relaxation technique and practice it daily at least two or three times for 15 to 20 minutes each time. There are many self taught methods of relaxation available on tapes and books.
7. Learn to breathe from your diaphragm. Learn how the body breathes and how your abdomen, ribs and chest are involved in breathing. Try to breathe from your diaphragm all the time or as much time as you can by paying steady attention to your breathing.
8. Learn to notice the advance signs of an anxiety attack before it becomes severe. Step up on your relaxation to bring about the calming response.
9. In a panic or anxiety attack, start breathing slowly, through your nose, and allowing your diaphragm to take part in breathing.
10. Say silently inside your head something reassuring and calming, such as, "I am becoming calm....It will take a few minutes. .. .I can handle it as I have handled it before. . .I am calm and steady. "