Chest pain still there with nausea. now worried if it isn't cardiac related is there something happening with my oesophagus?

Very well could be: If you have chest pain with nausea and have undergone an extensive cardiac evaluation, then it very much so could be gastrointestinal related. It is well known that because of "shared" sensory nerve networks, that upper gastrointestinal pain can mimic cardiac pain and vice versa. You would be best served to review your concerns with your doctor. Remember even anxiety could be causing this.

Need Evaluation: There are many cardiac and noncardiac chest pain, however, the exact etiology cannot be determined without appropriate testing. Noncardiac chest pain and he caused by reflux esophagitis, diffuse esophageal spasm, esophageal dysmotility, costochondritis, pleurisy, intercostal neuritis, achalasia, bronchitis, bronchial irritation. However, proper assessment and testing is the key.