Could Chest Pain, Fatigue & Insomnia Indicate Serious Health Issue?

Hi, I am a 21-year-old female; last year, I found out I am anaemic. I have been having chest pains for a while now; back in March, I went to see the doctor; he believed it was acid reflux at that time. However, in the past weeks, I have been feeling pain sometimes as if something is being pulled or squeezed, and sometimes, out of nowhere, it can be a sharp pain and stop, and then it will be dull pain kind of going to my left. I even feel pain under my left breast or right or in my armpit, but mostly on my left side. And my neck will be painful on the sides and have a pain at the back. And I have pain in my left ear. It stays for days and will stop and will again start being painful. And i have been struggling with insomnia for the past months, but however since last week wednesday, it is like my body wants to lie down. Every time I try to do some work, I wanna rest, but I still feel sleepy even after resting or sleeping. I have used some painkillers, but still. What could be the issue?