Puking?!

So September 1st through 9/10:2017 my husband and I were trying for another baby and then realized we weren't sure if it was the right timing so we stopped. Anywho my period is due in 4 days and the past two days I've been super nauseous and it's 2:30AM and I'm sick and puking not once but twice. Wtf is going on. Anyone else had this happen right before your period? I also took a pregnancy test 6 days ago and it was negative.