Same or different ovulation days??

Jenna • Wifey💍Mom of 2💕

I started using OPK's last month. I got peak ovulation on cycle day 12 last month (with 3 days prior of high fertility). I'm currently on cycle day 13 and still no peak but have had 4 days in a row of high fertility. Is it normal to ovulate on differently cycle days every month? Hoping I get my peak tomorrow...(I have a 26-28 day cycle).