Should I take a pregnancy test???

EmmaRae
I'm suppose to start my period today. I've been cramping since like Wednesday or Thursday. I lost my virginity on May 25th and on June 1st I started spotting but didn't start my period. I've been having a lot mood swings lately but I'm under a lot of stress. Really hoping it's just the stress that's causing me not to have my period. I've also been having really bad headaches. Yesterday and today I've been really sick to my stomach. Any advice??? Please help. I'm 20 and still not finished with school.