For the last week i've had trouble falling asleep. everytime i start to fall asleep i feel like i quit breathing. what could be causing this?

"Quit breathing": First thing that comes to mind is sleep apnea. Your General Physician may want to refer you to a Pulmonologist. A sleep study may be in order. Also important to have all Physicians that you see review all of your prescription medicines, OTC vitamins/supplements/additives, and recreational substances.

Can't Sleep: Not having all information ,symptoms or any other underlying issues.Its difficult to comment with certainty.Relationship of falling sleep- not been able to breath beside sleep related disorders could be anxiety. Lot of folks have panic and anxiety (some time Trauma Related) that lead to a struggle like that.Best recommendation an appointment with full evaluation.Good luck

?sleep disorder: Hard to sort out from information provided, but could consider panic reactions, sinus/ throat irritation, but also sleep apnea and even unusual presentation of restless leg syndrome. Worthwhile to fully track down if persistent.