I don't know what to think.
Congratulations on your bfp! I am so sorry to hear about your loss though, I know just how hard that can be. (((Hugs)))
It doesn't really matter how faint the line is, but it should probably get a little darker as time goes on. I don't think you will see much difference with only a day in between though. But then it might all depend on the type of test you are using. The only real way to know for sure what is happening is to go in and get your betas checked. I too wish these things were easier and faster and that there was a risk free way to know that all is well! Unfortunately you just have to take it a day at a time and things will work out, just hang in there. The one time I had just a faint line it got slightly lighter the next day and the following day when I went to the doctor it had dropped enough that it did not even show as positive for them. I had my beta drawn which confirmed that I had been pregnant but that it hadn't progressed. As long as your's are not getting any lighter then you are likely just fine.
Do keep us posted on how things go for you, and I truly hope that this is a very healthy and very sticky bean. :-)
Loving Mom to three
Loving Mom to three rambunctious