This isnt normal. You should go to the doctors as it can affect your sex life.
Mr.lucky66 is totally right, do what exactly what he said for this deadly disease to be cured. But seriously dude, don't worry about it. Its normal.
this is sir. whip it out every morning and face the west for one week at dawn . Stand there for 5 minutes and then resume your regular activities. Do this for one week to correct the problem.