2mm 5 weeks 4 days.

So according to Glow I'm 5 weeks 4 days, but my cycle might be more irregular than I thought.

Today I went for my first check up and they said it's too small to confirm the pregnancy so I'm going back next week.

From googling it I'm still not sure if I should be worried or not.

In the hospital they said nothing is necessarily wrong but just that the maths doesn't add up with what I told them about my cycle. Maybe I'm actually 4 weeks or maybe my cycle this month would have been irregular?

Has anybody else had anything similar?

What happened?