Cant breathe while sleeping in daytime?

hii im 24 yr old male. actually when im sleeping during daytime i feel that i cant breath. i ll struggle to breath to get some air just for sometime. at that time i cant open my eyes properly. before getting into deep sleep im feeling like this. during night time i wont feel like this type of probes. whats the problem with me,can any one tell me. no jokes i need correct answers,bcoz its serious.