Could I Be Pregnant?

Hey guys I need some advice..... my period comes one month then the next month it will skip. Last time i got it, it started and ended was 3rd-7th Of August. I took a test two weeks ago it was negative but I took it at night...I been feeling twitching in my stomach in different places I can’t sleep very well but I also started working night shifts but even a new schedule wouldn’t get in the way of my sleep ive had a loss of appetite only eat once a day I sleep better during the day somebody help!!!!!!?????