"Left in pain and sent home with no diagnosis"

I was sent to medical assessment unit by an OOH GP due to severe pain and breathlessness. After waiting 8 hours got told bloods were okay and was sent for a chest x-ray by a doctor. Got told by a nurse my bloods were okay and chest x-ray was NAD therefore I could go home. I had already informed medical staff that the analgesia I have been taking at home is not helping the pain and required stronger analgesia when admitted. I am now home still in severe pain and still have no idea what the cause of it is. 

As a nurse myself, I feel really let down as this is not good patient care and not the care I would expect to receive. Basically I have been sent home to suffer the pain with no further investigations. I am currently off work sick due to this aswell and no further forward to what is causing the pain. 

I understand how busy the hospital is just now, and this is no fault of the nurses they were great, however the doctor in my eyes did not give me the care or treatment which I would expect no results were discussed with me and no explanation given to what the cause of the pain was and sent home with no analgesia still in severe pain and left to suffer.