The last 3 days I have taken a HPT.
Congrats... No I wouldnt be concerned. With my last pregnancy I tested several times and got the faitest line that unless you looked at it just right you didnt see it. I was pregnant though and every thing was fine it was just early. So I bet if you really wanted to you could wait a week and do it again and get a dark line. but really you are pregnant either way. It may just take a while for it to get darker.