My Period Has Been Kind Of Irregular For The Past

My period has been kind of irregular for the past 2 months and i am 4 days late this month, and i have been experiencing symptoms like nausea, bloating, and i havent been going to the washroom. I have never had any sexual activity. I'm a virgin and ive never had a boyfriend and have never done anything with a boy, not even kissed, so im pretty sure i cant be pregnant but why am i experiencing pregnancy symptoms, ive been really stressed over these symptoms and being late on my period its all ive been thinking of for the past few days.