Ugh, i dont know whats wrong with me?

Im not PMSing i already got off and im not due for awhile haha but lately like these last few days ive been so irritable. Im not usually an overly impatient person but the littlest things seem to really aggravate me. Ive been crying randomly no more then like 2 minutes at a time.. I feel like i cant keep myself together. I had my period, so im not pregnant.. But i really dont know whats wrong haha. im 17, my stress level isnt super high and ive been sleeping fairly normally and eating well.. What is wrong with me!