Camembert

For the past few months, I have been having episodes that feel like panic attacks. My heartbeat accelerates and is sometimes irregular, I feel nauseated and faint, and I have a lump in my throat which makes me feel like I am choking. They can last for up to 4 hours.

Is this an anxiety attack? At the moment I think that is the most likely cause.If so, how can I prevent it?