Dilated !??

So went for my check up I'm 34 weeks and 5 days everything is great ,Quick question my doctor told me that I was 2 cm dilated and 50% . Does this mean that my baby could come early what are the chances?? I'm getting so nervous I don't want to walk or do anything I don't want her to come early.  But I'm definitely nesting .. Ughh so worried this is my third baby and I feel like I'm new at this