If you have a panic disorder, you get intense, sudden panic attacks. These attacks often feature stronger, more intense feelings than other types of anxiety disorders. The feelings of terror may start suddenly and unexpectedly or they may come from a trigger, like facing a situation you dread. Panic attacks can resemble heart attacks. If there’s any chance you’re experiencing a heart attack, go to the emergency room. It’s better to err on the side of caution and have a healthcare professional check you.