I wasn't ovulating when I had sex but my period is 8 days late.. Can I be pregnant?

[Smhd]

I'm a sexually active female who is on birth control. I had my last period on the 1st of September till the 7th. My birth control consist of having to take a pill every day for 21 days and taking a week break. I usually take my birth control pills every day, but during the last week before my break I missed a few pills, and I read that if more than 2 pills are missing during the last week, I should presume taking the pills without the usual break, which I did.
My boyfriend was out of town and came back on the 24th of September, so I wasn't sexually active after my period until the 24th. I calculated my ovulation day to be on the 12th of September and my fertile period to be from the 8th till the 18th of September, so I am not supposed to be pregnant.
However, I am 8 days late for my period which never happens, and I keep feeling like my period is about to come, as I am experiencing symptoms of mood swings and cramps, but it never does. I read that a lot of women feel their period about to come and it doesn't until they find out they are pregnant.
My question is, what are the chances that I might be pregnant? And if there's any way to provoke a period to come? I am freaking out because having a baby is the last thing I could do.. I am young and I live in a country where having sex is not even an option.
I'd really appreciate a quick honest response.. Thank you