Hi Arielle, I'd say you're between 10-12dpo. You may be able to test, but it might be too soon. You can never be 100% for sure when only using OPK's. I've had a positive OPK 3 days before I actually ovulated before. I've even had a positive OPK, then the next few days it's negative, but then it's positive again, meaning I didn't ovulate the first time, and ovulated after the second positive. The only real way to know where you are in your cycle is to do BBTs (basal body temperatures) along WITH OPK's. There's a link in my signature to my ovulation chart, where you can sign up too and track your cycle, if you don't get your BFP this cycle. I hope this is it for you though! Good luck!!