Pregnancy? Or just late?

I’m freaking out. My boyfriend and I had sex about 23-24 days ago and my period should have started yesterday (it’s normally not late, but I did have very irregular periods about 5-10 years ago) and it didn’t and no sign of it starting today. I took a test today with my coworkers there for support and it instantly showed up negative. We let it sit and watched it another 5-10 minutes and it was still negative with no faint line. Then one of my friends started saying she couldnt tell she was pregnant with either of her girls until she was 6 weeks. I’m just so scared. I don’t want to be pregnant and I don’t have time for a baby. I work all the time and I’m always under so much stress. My body weight has also fluctuated a lot in the last two years so I don’t know if that can cause anything and I’m just freaking out and I need some advice or anything 😢😢😢😢