Really worried about my mom's health, what is wrong with her?

She gets these crushing sensations in the chest, today was really bad and lasted for around 10 minutes. She said it's like a tightening of the chest and she's afraid to breathe, so she went to lay down until it passed. There's no other symptoms other than a crushing sensation in the chest, and she gets them once every couple of months. The last time she felt this was 4 months ago. Is this angina? And is this a sign that she's a candidate for future heart attacks? She had an ekg and did a whole body checkup and the doctors says she's fine. Well obviously, she's not fine. I'm really worried about her and if anything happened to her, life would not be worth living anymore.