Possible miscarriage?

I tested positive on Monday which was a surprise because I was on birth control but I wasn’t the best about taking it regularly. I was shocked but my partner and I were actually really happy once the thought set in.

Last night I started having severe cramping and bleeding. I was checked out at the ED, and they basically said I need to follow up in a couple days to see if my HCG levels increase or steadily decline.

Preparing for the worst but I just wanted to know if it was still possible the levels could increase?

Or has anyone had a miscarriage and had gone on to have a healthy pregnancy after they were cleared to try again?

(Not looking for medical advice just some hope)

Thank you