is it possible?!

Hey chickaas! I had sex May 27,28,29th and all three days my SO ejaculated inside me. My period is very irregular and has been since it first came into my life (LOL). My last period was May1st and ended two weeks after. I'm scheduled to come on again in about 4-5 days according to glow but I doubt it. I've been feeling nauseous, back has been killing me and I've been really tired. Sooo I took a pregnancy test... it came back negative. Is it took early to test? How long should I wait to test again?