So confused

So according to this app i was supposed to start my period the 21st. And well I'm late but it said I ovulated the 6th through the 12th but since I haven't started it's changed my ovulation date to the 8th through the 14th so my question is is it possible that I got pregnant in the time frame of the 8th through the 14th and I'm pregnant but it's just to early to show up on a test yet? also I took a test last night and it was negative and I took one early this morning and again negative so I'm so confused my periods are regular and the past 2 months have been early 4 or 5 days so all this is blowing my mind.