just because your level is over 1000 doesnt necessarily mean you will be able to see something, you are still really early and usually most dont see something until around 6 weeks. good luck!!
When I was that far along we saw the speck thing too. but knew I was pg. from a ++ test.
I went back a week or so later and we saw a tiny sac and heart beat!
Brown blood is generally not a concern, as it's old blood just making it's way out.....If it were bright red, that's more of a concern. I've never had an U/S that early, so I'm not exactly sure what they would see....I had mine at 8 weeks and there was just a little blob there......
As far as the Lovenox goes, call your Dr. before starting it in the am....just to be on the safe side.....
Best of luck!
At 4weeks its still very early to see anything! Good Luck at your next u/s and beta!! If your dr. told you to start lovenox, then do. :o)