What Causes Pain In Back Of The Throat With Nose Bleed?

The back of my neck hurts, i've had a dull headache that comes & goes my nose has been bleeding a few times lately & i can't take a deep breath in when i try to it's like something blocks me halfway through it from taking it any deeper what's wrong i had a complete blood count done, all normal except low iron & vitamin d had a chest x ray done, all clear could the vitamins cause some of these problems? what's wrong with me