Pregnancy or not

So between the 9th - 17th I’ve been feeling really nauseous, I ovulated on the 8th. My period was expected to come on the 24th and it usually does but this month i got it on the 20th and had really really really light period and only for 3 days when usually it takes me 4 or 5 days to be completely over. It’s the 23 and NO more bleeding at all. Well I’m still feeling nauseous.

My question is could I be pregnant or not? Because one of my friends before she found out she was pregnant she had her period for 6 months and when she found out she was already 5 months.

But i’m pretty sure I’m not since my period came on the 20th...

I’ve heard stories from people that they had period during their pregnancy...