So long as you're still late you could be. If you get another negative urine test, wait a week. If your period doesn't show, call your doctor to request a blood test.
Yes you can be. Some women get negative tests even when their close to 6 weeks pregnant. I'm in the same situation. I would be 5 weeks 2 or 3 days I believe. I'm not too sure but last period was 2/1. It's 3/11 now. I had some spotting but it stopped then came back but now is like a creamy discharge with a tinge of brown. (tmi ??) I tested this morning and got a negative. But, since I don't have a period I am still in the game. =)