Is this a sign?

My cycle is usually 28-30 days or a little bit more depending my my level of stress (I'm a student so around exam season it's usually a bit late). I had my period from the 24th to the 28th of May and then I had it again from the 15th-20th of June. That was only two and a half weeks later but usually the calendar adjusts so I am currently two days late and worried because I'm feeling a bit nauseous sometimes and bloated and my boyfriend and I do have sex so I was wondering if I should take a pregnancy test or not