[Sacamuelas]

I agree with all the previous posts. The most likely etiology of your symptoms is some sort of impingement or inflammation associated with the ulnar nerve.

The trauma that causes this is often not in the catagory of major/life changing accidents. Chronic trauma can occur from simple daily actions that most on this site experience quite often. When your tired, some people will rest their heads onto their wrists and support the weight with their elbows on a table. Another instance that isn't as avoidable, when lying prone and using the elbows as a bi pod to support the weight of your head and binoculars when glassing an area for a long time period. Both of these type actions can aggravate an ulnar nerve inflammation by causing direct trauma.

As discussed above, the ulnar nerve symptoms you describe can also be caused by a very similar situation to what most know as carpel tunnel syndrome. Of course, carpel tunnel is associated with a different nerve and anatomical area, but the overall understanding of what is happening is the same.

Follow The Reaper's advice, go get checked and avoid unnecessary trauma to your elbows in the future when that is avoidable. Especially the bad habit of resting your head on your hands when tired.

Good luck