5 Days of Positive OPK?? Confused....

Hi everyone. I posted this in the ovulation group but haven't received a response yet so I'm hoping someone here can help. I'm 32 yrs old and this is the first month my husband and I are TTC. I've been using an opk that lets me test for 20 days because my cycle always ranges between 30 to 40 days so I wasn't sure when I'd be ovulating. The tests were negative until Feb 1st when I got my 1st positive. But now the tests have be positive all week! Is this normal or am I reading these wrong? This is the picture of all of my tests this week. We've been BDing all week although I know most people don't get pregnant the first month of trying but a girl could hope, right? Thanks in advance for your help!