When should I test?

Hello, so I had my Iud taken out this pass December and we've been ttc every since. I've been downloading apps to keep teack of my cycle. According to the glow app I ovulated on the 23rd of Sept. We were successful in getting two session in that day and once the day before.

Soo I had some cramping in my left side yesterday and an upset stomach today I'm getting anxious waiting for real symptoms. So any advice on when I should test so that I'm not just wasting time and money?