I agree with Kcraig - I know it's hard to stay hopeful, after all we've been through to get here we're conditioned to expect the worst, but almost every donor pregnancy I'm aware f had some cramping and bleeding in the early days. In my case I went and had a few glasses of champers because it was DH's birthday and I thought it was all over, turned out it wasn't (so I felt terribly guilty!).
Take it easy if you can and see what the next few days brings. Big hugs to you xxx