From what I understand, small fibroids are unlikley to cause serious (or any) complications in pregnancy.
I have several very large fibroids (two of them are 11+cm each) and I'm still too early in my pg to know if they may cause difficulties in terms of room for the baby to grow (they're outside the womb, so hopefully that won't be an issue) and delivery. The obstetrician I spoke with at UCH last week suggested there's a greater chance I'll have to deliver via c-section. But again, at just nine weeks, it's too early to tell.
Fibroids are hormone-fuelled, so they tend to grow in pg. If they get so large that they outgrow their blood supply, then they can degenerate, which, from what I've been told, is a savagely painful process (some women have to go on morphine for the pain).
I asked the obstetrician about increased risk of bleeding or miscarriage due to the fibroids and he said that there really isn't any evidence that fibroids affect the chance of either. He said if bleeding or mc occur, some people point to the fibroids in search of a cause, but that doesn't mean they are the cause.
I had some serious pain at about 5 weeks that I assumed was my fibroids. A couple of days on paracematol and lots of sleep took care of it, and I've been fine for the past few weeks (except for steady mild nausea).
So I guess you really need to talk to your doctor/mw again and find out how large the fibroid is and where it's located. Hopefully it's small and won't be a problem. Good luck!