Hi dere...usually over thinking and being under stress gives rise to headache. You may be depressed or may b not ...but dat depends on other symptoms...if u r feeling sad most of the time..if u r not able to enjoy wat u usually liked ...if ur confidence has gone down or u r pessimistic about future...if u r getting fatigued easily and do not feel energetic for most time of the day.....then probably u may be depressed.... Hope this helps..but feel free to consult further in follow up section. Thanks