Do I use Plan B? Please answer

My boyfriend and I had protected sex on Saturday (Oral contraceptive, condom/lube) and he busted outside of the condom and NOT in me.

My birth control prevents ovulation, but we had sex on my highest day of a fertile window (ovulation) and my stomach has been hurting ever since.

I have a Plan B where I can take it up to 5 days, but it gets less effective and today is the 5th day.

I’ve been eating poorly these last few days, so my stomach is more of a gassy and rumbling/crampy feelings and my breasts have been very sore (which is a symptom of ovulation, which makes me feel that because this is my second month on birth control, it didn’t prevent my ovulation date). I don’t have time today to get a pregnancy test and i don’t think it’s even late enough to check. My period is supposed to start in about 10-12 days.

What should I do :/