I sometimes have sharp pains in my head that come and go. do you think its a reaction to something or something else?

Head pain: The pain is coming from something; however, worrisome pain usually does not come and go but would steadily increase in frequency, duration, and severity. It could be tension headaches. See if massaging with your thumbs the small notches in the bone above your eye close to your nose. Massage the notch for 30 seconds when you get the pain. If it persists or increases seek medical advice.