Preggers or nah

So according to my glow app i was supposed to start my period on Wednesday. Then i was late and realized that my period last month was for the 21st so i assume that it was just on a different schedule now...synching up with someone from work.

So on the 17th i took a test...neg. which is fine! But still 3 days late with nausea, sore breasts and my dogs keep sniffing my belly.

Thoughts?!

Am i pregnant or should i wait to take another test?