Eric was complaining of chest pain and palpitations.
She says his heart rate was racing at times, and when she tested his oxygen level, it was low.
Obermeier immediately called Eric's mother, who took him straight to the emergency room.
He was then transferred to Children's Hospital of Philadelphia.
Eric was diagnosed with pericarditis - an inflammation of the lining surrounding the heart.
It's most commonly caused by a virus. It's possible it was related to the pneumonia which put Eric in the hospital for two days in December.
Eric spent two days at CHOP. He was treated and is now on the road to recovery.
Eric's mother, Jessica, is incredibly grateful and is praising the school nurse for her quick action.
Obermeier says she was just doing her job, but is also thankful Eric is okay.
The principal of the school, Travis LaFerriere, says he knows it's her job and it's important especially with kids.
"But still it makes us very proud that she pays close attention to details and she essentially saved a kid's life," said LaFerriere.
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