“Did the ER misdiagnose me with GERD?”

I don't have a primary doctor yet but the ER diagnosed me with GERD because I had sharp chest pain and a rapid heartbeat out of nowhere. They did a blood test and a common chest x-ray — no barium swallow test or endoscopy, and they diagnosed me with GERD. They prescribed me a PPI called pantoprazole ever since I took it once a day, I started getting dry coughs. Tums gave me a stomach ache and when I cheated and ate yellow rice and acidic juices, I felt much better than sticking to a bland diet. I had missed my period for a month and suddenly the chest pain came and I got my period. That's ever since I had this sharp chest pain. Now the ER diagnosed me with GERD so idk if it's a misdiagnosis or not I did get a burning sensation in my throat and chest here and there but idk if that's because of anxiety.