Positive OPK

I hope this is in the right group. If not I apologize. On October 22, I took an opk, and it came up positive. My husband and I made sure we BD that night. I kept taking opk for a couple days after that just to be sure, and they were obviously negative. Well, I’m suppose to start my period today, and I took an opk today and it was positive! I’m hoping this is good news. My husband and I have been trying for 3 years to get pregnant. I’ve taken OPKs in the past, but this is the first month that I’ve ever gotten a positive!

My question is: Is it possible to be pregnant if I have a possible opk on the day I’m suppose to start my period?