Suggest Treatment For Headache
Several possible causes.
Detailed Answer:
I read your question carefully and I understand your concern.
I hope that when you say you have no fever you have measured your body temperature by using a thermometer, otherwise a mild rise in temperature might be missed.
Also a blood pressure measurement is recommended if not already done as its fluctuations can cause similar symptoms as well.
Otherwise those symptoms do not suggest any serious brain related condition which are usually associated with many other symptoms. The most probable cause in that case would be tension type headache, the most common primary headache (primary meaning with no identifiable cause), often triggered or exacerbated by stress and anxiety.
Other possible causes might be sinus related headache (but usually associated with nasal congestion as well), or visual issues which could also cause some mild headache due to muscle tension.
For the moment I suggest the use of over the counter painkillers like Ibuprofen (but after blood pressure elevation has been excluded first).
Of course if any new symptoms appear, I remain at your disposal for other questions.