Ovulation?

Is there any way at all to know when I ovulated without taking my temps? I noticed the line starting to get darker on a Saturday the 27th... Sunday I got a peak result on the more expensive Clearblue brand. Once that happens it is locked for 48 hours.... but I got blaring positives Sunday, Monday, and Tuesday morning with the cheapies. Tuesday afternoon it was still dark but not positive. Any suggestions? Trying to figure out how many days past O I am today. This app is showing I O’ed Tuesday so I’d be 8 days past today according to that.