Miscarriage?

Sarah-Jayne 🏴󠁧󠁢󠁥󠁮󠁧󠁿

I'm 21 weeks and woke up at 5am with a terrible pain on the lift lower side of my tummy. It lasted about 1hr. Its fine now, could this be an early sign of a miscarriage? How long after pain should you expect to see a bleed? I'm so worried 😔