Headaches can be caused by many different stimuli, including emotional stress, fatigue, medication use and acute pain.
The presence of left hindbrain pain, with varying length of onset, can suggest different causes.
If the pain is prolonged in the left back of the head, most often consider a migraine, where the headache is usually unilateral, often occurs on waking and can be accompanied by nausea, vomiting, photophobia, phonophobia and sensitivity to stimuli.
If there is occasional pain in the back of the left side of the head, it is most often considered a tension headache, due to persistent contraction of the muscles of the head and neck.
Other possible causes are left-sided intracranial occupying lesions, vascular neurological lesions, and trauma to the left side of the head.
However, it is difficult for the general public to determine the presence of these disorders on their own, so if you have persistent left hindbrain pain that is difficult to relieve or recurrent or even gradually worsens, you should seek prompt medical attention to clarify the specific cause so that you do not miss out.