How many days should you have +OPK?

Kayla • Sun, Feb 02 2014 • Married & we had our perfect baby boy on 03/21/2015, Pierce Huntlee. He was 7lbs 10oz, & 19.5 in 💙

I got my surge yesterday, I thought.. I have gotten positives at 10:00 am, 2:30pm, 11:00pm all yesterday, and then positive at 8:30am this morning. Is this normal? Or should you surge then it gets fainter? Mine is getting darker! Lol, help!