Lightheaded for a few days, heart rate erratic but always regular. possible palp. anxiety disorder? took some heart tests, negative. clean for all.

Could be: It could be. You should consult with a psychiatrist and/or psychotherapist, to look into treatments for anxiety disorders, including medications such as ssris like Celexa and zoloft, (sertraline) but also meditation, yoga, and exercise.

Anxiety disorder??: If everything ok physically, i'd suggest consulting with a mental help professional to help you deal with your symptoms.