Could I still be pregnant?

Every month I get my period 9-12th. The 12th the latest. last month (June) I got my period on the 14th which is not normal I'm never late. I can't figure out if I'm 6 or 8 days late (today July 20). Glow says I was suppose to start on the 14th so I'm saying 6 days late? I took a pregnancy test last night it came back negative (I also drank a ton of water) I took one this morning again using my first urine and it came back negative. I used clear blue. Is clear blue accurate or should I try another brand? my husband and I use pull out method, he wants another baby me I wouldn't be mad.