I have anxiety. I went to ER once, and they listened to my heart with a stethoscope. I wanted EKG. They hooked me up for 1 min and reassured me. I am 15. But I took a glimpse and automotive computer reading said abnormal EKG. Why was this?

It's normal for your heart to beat fast with anxiety. If it said abnormal EKG it could be many things, it could have read when they were removing the electrodes, just many things, remember, it's just a machine. If the doctor looked at it and said it was ok, chances are everything is ok.