Help !

Hey guys! I recently started taking plan b for the first time and I have a couple questions. My boyfriend and I recently were active 4 days before my ovulation and he was with protection but we think he used it wrong. We got a plan b the same night just to be cautious. I had my period a week before that. And I got it again for three days the week after which I told it was normal due to the plan b. We got active again two weeks later and we used a condom and according to my calendar, I didn't ovulate yet still had two days left. The condom was a little leak don't know if it was from him or me, because I got a little anxious and we took another plan b, same night as well. It's been three days and now I'm experiencing back pains and cramps. Is this normal due to the plan b or should I be concerned? Will I get my period again this month?