Pregnant but negative tests… please read

Hi all,

I’m really concerned about my friend as this has been happening for months- here some info:

‼️She’s 28 years old

‼️She has a 10 month old and not on contraception

‼️Her “periods” have been all over the place and a lot lighter/longer/shorter than normal

‼️She’s falling asleep at work EVERYDAY

‼️She’s got heartburn ALOT

‼️She’s gained quite a lot of weight round her tummy (she’s also admitted this herself but she put it down to covid lockdown)

‼️ She says she can feel something moving in her tummy?! 🧐

I said I think there could be a chance she’s pregnant, she did 4 tests all negative

I also have a friend of friend of a friend who gave birth to a surprise baby! Who had NO idea she was pregnant until she gave birth on the bathroom floor! She didn’t know because her tests were all negative!

I’m trying to make her see sense to see a doctor to just double check by blood but at the min she’s not having any of it!

My question is, how rare is this?? And has this happened to anyone on here!?

TIA 😘 xx