Don't panick. Call your doctor and ask them what to do. I googled and found heaps of very good information on measles. My DD2 was recently sick with what they think was a mild form, although she was quite sick.

What I would look for is initially unusual crankiness, elevated fever (please keep a very close eye if bub starts to get a fever). Red marks in her mouth is a sign too and I think vomiting maybe a sign.
I really don't think you'd have come in close enough contact though but it is good to be informed just in case