Hello. I Have Been Having Burning Sensations/pressure Around My Heart

Hello. I have been having burning sensations/pressure around my heart for the last 4 months. I have had 4 EKG's and they were all normal. My GP thinks that I have Acid Reflux. Do you think it could be a heart issue? Also - I am a little light headed at times. I take medicine for my thyroid, onglyza for pre-diabetic and now this acid reflux medicine. Just wondering if I should follow up with an endocrinologist or internist?