Chest Pain And Heaviness

I am 39 years old and have been having chest pains and problems taking a deep breath and it feels at times that someone is sitting on my chest. This has been going on for at least 1 year now. Sometimes it is worse than others. My doctor has me on nexium for gerd and he tells me that is alot of my pain. I took a stress test about 3 months ago and had blood work done--everything looked fine. I quit smoking 6 months ago. I am just so frustrated that at my age I feel so bad and it is just suppose to be" normal". I do have alot of stress in my life and my work does require some light lifting and some walking also, both my parents had heart attacks but much later in life. I just dont feel this is normal! If anyone has had these problems or might have some suggestions I would appreciate it. I feel it would help me to suggest to my doctor or decide if I should find another doctor.
Thanks,

danamac