Hi My Name Is Bree. I Am Currently 19 Years

Hi my name is Bree. I am currently 19 years old, and going to be 20 this upcoming June. Lately, for the past couple months or so, I have been experiencing dry heaving daily. It happens most in the morning when I am getting ready for work, but sometimes throughout the day also. I never actually throw anything up, just a a lot of gagging/dry heaving. It only lasts like a minute and then goes away. I have to kinda sit there and take a couple deep breaths. I did recently take a pregnancy test, about 4-5 days ago that i bought from Walmart. It was negative, so I am not sure what else it could be, so i was wondering if you might have an idea? Far as i know, there is no medical history that would be relevant. If you have any other questions, I am happy to answer. Thank you!
-Breeb