I don't know what it could mean, but I had a bad nightmare once where I woke up gasping for air, because I had quit breathing in my sleep as well. mine was caused by being overmedicated on P-doc meds, and then quitting cold turkey. now I have sleep apnea as a result of the experience.

sometimes a deeply rooted fear, concern, worry, or other thought can manifest like your dream, find someone to discuss it with and see if you can figure out what caused it.