Is this a panic attack or what?

not exactly a panic attack but yes, this is a psychological effect that is taking place. As you experience a chest pain, your brain instantaneously associates it with the closest link that it believes you to have, a heart attack. These are the the ways, your brain starts to recover from the initial shock of irregular heart beats( so its taking more precaution this time.) And it is common for the symptoms to get worse as you give it an excess of attention, that is not required. So whenever you get the next symptom, try to divert your attention from it, like watch something entertaining, etc. Panic attack would be when you can actually experience the adrenaline rush, over stressing your body, like deep uncontrolled breathing that occurs without your command, watering of the eyes etc