Pregnancy scare!!

I had sex on my second ovulation day and I'm on the pill, my boyfriend finished inside me but I'm unsure if I'm pregnant or not because I've been on antibiotics and the doctor warned me that they can clash with the pill. I've been feeling nauseous, teary and my back hurts a lot.. Should I take a test just in case because I'm overthinking too much maybe! I'm scared šŸ˜©šŸ˜”