Hi, I Am Not Sure If I Am Pregnant Or

Hi, I am not sure if I am pregnant or just about to get my period. I have only had sex once about a month ago, I am now having a lot of pain, cramps, diarrhea, and vomiting that I would normally get the day before my period starts and my tracker said I should have started yesterday, so now it is 2 days late. The cramps I am getting are random but extremely painful to a point where I am crying, but after a few minutes they go away. I have thrown up 2 times in the past 2 days, and have had diarrhea 4 times. Please lend your advice if my period is just being late and my symptoms of PMS are just worse than normal, or if I should get a pregnancy test.