Late HCG levels?

First time mum

Hi

My cycle is always 28 days. I’ve always been so regular.

I’m now a week late and I’ve taken pregnancy tests and they’re all coming back negative.

I’m really confused as this is very unusual for me. I have different symptoms to my usual pms (different type of cramps, shooting pains from my armpits to my boobs)

Has anyone had a late positive pregnancy test result before? Is it worth requesting an HCG blood test?

Thanks