Do people who are pregnant without realising it, REALLY not know?

Currently pregnant for the first time and there is absolutely no way I would not be able to tell I’m pregnant. My boobs are enormous and sore, and I feel utterly dreadful.

All my friends who have recently had babies or are pregnant have reported similar - horrible morning sickness, headaches, nausea, dizziness.

It’s also impossible to have a period when you are pregnant.

So it’s got me wondering - do people that don’t know they are pregnant REALLY not know? Or are they just trying to convince themselves that their symptoms are something else?

Moving baby - gas

Sickness - not well

Weight gain - eating too much

I have a friend who did this - knew something wasn’t right but ignored it until it came up at a routine medical appointment. She was 27 weeks!