Early Period ??

I'm on birth control , and I usually get my period in a pattern . Starts one month , skips that following month , so on and so on. My last period was last month (July) 🙄 it's August now , and all of a sudden I begin spotting. Has anyone had this problem. Also ,I missed a few pills but I took them soon as I remembered. Can that be the reason why I'm spotting ?