Talk to Urologist on Sexual Problem

Asslam o alaikum Doctor. I am 35 years old and it's been 3 years since my Marriage and i have 2 kids.i am facing Erectile disfunction.my penis doesn't get fully erect and i have short duration marital intimacy.I also have stomach issue and have burning sensation. i have also some other problem. 1.Trouble sleeping at night. 2.weight gain and weekness 3.Neck,head and Muscle pain. 4.feeling tired most of the time. please suggest some Medicine which improve my energy and suggest some medical test which diagnos why my penis doesn't get fully erect.