Just spent 4 hours in the emergency room.

I woke up around 1:30 this morning to soaking wet underwear like I peed myself or something so I went to the bathroom and just immediately started bleeding. Like enough to almost fill one of my menstrual cups. It was bright red and horrifying. I've never even bled like that on my period. So my husband took me to the ER to get checked. They did a pelvic exam and found that my cervix was slightly open and said I was likely going to miscarry. But then they did some ultrasounds and saw the embryo. Everything looked good with that- there was a heartbeat and it was right where it needs to be. My hcg levels were really good-around 20,000. Dr said I'm a threatened miscarriage though and need to be on pelvic rest and that I need to see an OBGYN ASAP. (This was my first time seeing a Dr about my pregnancy) So basically I was wondering if there was anyone on here that has had a threatened miscarriage that ended up carrying to term without too many problems and if you have any advice or anything?