Brief Answer:
Consult an ENT specialist.

Detailed Answer:
Hi xxxxxx,
Thanks for the query under Health care magic platform.
I have read your query & understand your concern.
You have only smell of blood from your nose & that too only while bending...there was never XXXXXXX bleeding from nose.This strikes few possible causes-
- You had posterior nasal bleeder( which is high & deep in the nose) .. where blood flows down the throat & is not seen flowing through nose.It also has possibilities of recurrence( explaining intermittent presence of smell)
One point to be noted is there would be black colored stool following the experience of smell .or the bleeding would be very small in amount.
Possible causes of such episode are trauma( hit ) or high blood press.You do have history of hit 6 months back..a very rare possibility.
-A small collection of blood ( haematoma) following the 6 month back episode of concussion.. can give you such smell .
- You do not have any symptoms , but a para nasal inflamed sinus can cause drainage of fluid collection inside in bending posture .
- It can be just a psychological feeling that follows the experience of brain concussion .
Well whatever the cause is, you need to exclude them by taking an expert consultation of ENT specialist.It would either exclude or find the possible basic problem followed by specific treatment , or would clear the fear/ doubt from your mind ,few sittings of psychotherapy may be needed .
I hope, the answer was informative & useful to you. Any follow up query is welcome.
Thanks.

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Brief Answer:
Can be actual blood engorgement in nose or an Aura

Detailed Answer:
Hi xxxxxx,
Thanks for the follow up query & added information
One thing is for sure that the blood smell is due to actual blood/ engorged blood vessels of nasal mucus membrane OR it's a psychological feel that you get in certain body position.Looking at the issue to be related to head ache I can think of following possible causes-
- Allergic reaction with sinusitis /nasal polyp/high blood pressure/refractory errors of eye causing eye strain /Anxiety- tension head ache have been already considered.In addition -cervical spondylitis /Migraine / epilepsy( just a possibility ).
Last three causes have typical momentary experience( aura) preceding head ache , which can be a blood smell in your case. From this .
The management requires consultation of experts. I would suggest to visit your family physician to start with.. who would examine you to get primary impression of cause & refer you to needful specialist OR start specific treatment as per need..Treatment would have object to remove the basic cause & treating your head ache.
I hope that satisfies you. Any further information you need, I would be happy to help.
Thanks

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