Thank you for saying you have already been checked medically. That is the right order to do things in, and it means we can talk about this without wondering what else it might be.
What you are describing sounds like a panic response. The short version of the mechanism: your body prepares for danger before your mind has decided there is any. The heart rate and the breathing are the preparation, not the illness. That is why a normal ECG and a terrifying experience can both be true at once.
The reason it repeats is usually the second layer. After the first episode, meetings stop being neutral. Part of your attention starts scanning for the feeling, and scanning for it makes it more likely. That loop is the thing counselling actually works on, and it responds well.
One practical note: avoid the temptation to stop attending meetings. Avoidance shrinks the problem in the short term and enlarges it over months.
This is general information in reply to a public question, not advice about your own situation, and it does not create a client relationship. If you are in immediate danger, contact emergency services.
