Fasenra for eosenophillic ashma

I began the initial load of Fasenra, and then began the injections every 8 weeks. After my load and I had my first injection that began the series, I had a terrible reaction of chest pain that radiated to my jaw. It lasted 15 minutes than I was seemingly ok. The doctor has said no more Fasenra, and they ask me to go to emergency room and be checked. They found no problem, and now I'm scheduled for heart testing. If these test are ok, I want to try Fasenra again, as I feel much better with it. Has anyone else had this reaction? how can I find out the safety of this drug. I could breath fine and no other issues.