I am 25 years old. Female. Height 5"7 and weight 143 pounds. I started developing a strange pain on the left side of my chest. The feeling is really tight and I feel a hot sensation (does not burn, just feels hot). This feeling comes and goes and started to get worse last week. I went to the ER and they performed an EKG which came out normal, an X-ray of my lungs which came out normal, and checked my blood work which also came back normal. They gave me a foamy white drink because they though it was acid reflix but the hot sensation did not go away. I left the ER with no diagnosis and it has been about 6 days and the feeling still comes and goes. I am not sure what is wrong with me. It just gets tight on the left side and then feels hot and this happens throughout the day. Not just on an empty stomach or after a heavy meal, it randomly comes and goes. I feel like I am under a lot of stress with work and my personal relationship so I dont know if this could be a factor. I feel since I went to the ER than there shouldn't be anything major wrong with me but I dont know if this is true. One thing I should admit is that I am a smoker. I smoke about a pack every three to four days. I have quit smoking since I went to the ER and tightness in my chest continues. Any suggestions would help. Thank you!