Ovulated early and got my BFP!

I took an ovulation test 10 days after the start of my period and the test was not peak, but high. We had sex that day and the day before. I tested the next day and it was low. We had sex that day and the day after just to be safe. Apparently I had an early ovulation because I got my BFP at 3 weeks, 3 days pregnant!!! Had I waited until the fertile window I would have missed ovulation!