Hello!
Thank you for asking on HCM!
Your symptoms seem to be related to anxiety. 
Gastro-esophageal reflux can not be excluded either. 
Anyway, I would recommend  consulting with your attending physician for a careful physical exam and some tests: 
- a cardiac 
ultrasound to examine your heart function and structure
- an ambulatory 24-48 hours ECG monitoring to examine your heart rhythm trends during a prolonged time
- 
complete blood count for anemia
- 
thyroid hormone levels for thyroid dysfunction
- blood electrolyte for possible 
electrolyte imbalance. 
You should discuss with your doctor on the above issues. 
Meanwhile, I recommend continue taking 
buspirone. An antiacid can also be helpful, in case of gastro-esophageal reflux, which can trigger your symptoms. 
Hope to have been helpful!
Kind regards, 
Dr. Iliri