has anyone else felt this?

Tracey
Im 21 weeks and throughout this pregnancy I've had a lot of acid reflux and heartburn. Ive never felt actual burning just on my heart though until all morning today. I googled and got really scared because I read it can be a heart attack or pulmonary emobolism. I'm wondering if this might be a new heartburn symptom or if it might be something more serious 😞  Anyone felt anything like this before? 
Thanks in advance 💕