I've had dry heaves in the morning. It is somehow directly related to pollen and the body reaction to it. I have them every time the grass cutters come around. Even If I am driving and I go past someone cutting a lawn I am affected and get dry heaves. Also, my system from sleeping overnight gets backed up with flem and absolutely makes me puke until I choke it out. Right now I am fine, but I suspect your problem is related to allergies. It has been a very bad year for anyone allergic. I live next to a conservancy wooded area, which means that almost anything is growing out there.
Note if anyone of your neighbors has been cutting their lawns and on days when pollen counts are high. (Ragweed at this time of year.) The heaves may be directly related.
Also, my hair was falling out too!