Highest percentage for pregnancy day.

I am a mother of an almost four year old little girl. Getting pregnant with her was easy. Literally she was completely unexpected. Now that I am ready to have another I am terrified it won't be as easy. So I thought I would follow my calculated highest percentage days and make sure to have intercourse. I thought I could do it every day during my ovulation timeframe. But between my daughter, working, working out, and being romantic with my spouse? I found that by my highest percentage day I was just too tired to do anything but sleep. So I completely missed it!! Now I'm kicking myself!! I guess my question is has anyone else missed that day  and still found they pregnant? I know it's just one month but I've been waiting for three years to try and concieve and I am just overly ready for baby #2.