Spotting few weeks before depo

Lena

First depo shot was in may the 26th. Me and my boyfriend didn’t use condoms for a while till recently. I was craving on one said like ovulation cramps so we started using condoms again. But today I started spotting. I’m due for another shot in the slot of August 11-25. When I first got my shot I was on my period. Second month I didn’t have a period. I had no spotting throughout until now. Has anyone had this or does anyone have an idea??