Sleep issues. This? so can i take this?

I have a sleep issues since last three years... I don't feel rested or refreshed in the morning despite long hours of sleep...I feel like I m having a light sleep and I don't go in deep sleep...sometime my sleep was interrupting...I feel very exhausted in the morning. I have a very low energy and i dont like starting a day.. I have check my b 12 level it was normal 424 and my vitamin d3 level is quite low 13...My digestive system is also affected and my appetite is low also...i don't take any sleep O medication till now as I am scared of its side effect and it's habitual...so my d3 level is quite low...it is due to this? Or my be some other reason...I am having anxiety also sometime..I have a heard that magnesium supplement is good for sleep...so can I take this?