Missed period.

So, hey fellow glow friends... so I’m usually regular with my periods. 5 days a month, well I didn’t get my period at all in April.. maybe it’s just late? Idk.. I’ve never missed a period. I went to the doctor three days after my boyfriend had sex but they gave me a pregnancy test but it came back negative. I’m going to try to see if it comes this first week of May? If it doesn’t I’m going to take a test. Also me and my bf has sex three times in March and a few times in April. I been experiencing really bad nausea as well.. just thought I throw that in... any thoughts ladies?...