Pregnant ? Or period ?

So, my boyfriend and I had sex at the beginning of the month. The 6th to be exact, I was on my period at the time; and we didn’t use protection. No he didn’t finish in me.) And this was after ovulation. When my period ended, I ovulated again on the 14th of this month.I watched him, finish and none got in me. My cycle is about 21-22 days, and it’s normally pretty accurate, if not a day late. But I’m supposed to start in 3 days. My boobs were hurting and I was cramping some during ovulation, which I thought was pretty normal. But now, I’m feeling nauseous; and again my boobs are pretty sore. Am I just over reacting? I’ve just never felt nauseous before my period, or on my period.