Hi Renstar,
Unfortunately i only have a "yucky" story to tell regarding faint lines and low hcg....

A few months ago i had a very similar thing- only my tests took awile to show- so i started to think it was evap lines- but i got about 5 of them. When i went to the dr i had my levels done and the next day i was called in to the dr's (a lot nicer than what happened to you- i didnt think they gave results over the phone?!)
AF had already arrived that morning- but i went in anyway to be told that my levels were 9 - and the dr was actually calling me in to say i might be preg!! (WTF??) When i told him i was bleeding he changed his tune and told me i was most likely having an early mis carrage due to not implanting.
A hcg level of 2 is not pregnant but anything above is considered "maybe" until it gets to the high 100's then its definate and the level doubles (approx) each day as the preg progresses (hence why you can test to see if its all still going good in the early days)

IF AF has not arrived (judging by your ticker not due for a day or two) it may be too early for the test to show (MAYBE not sure what the absolute neg or pos test is)

I would go see another dr and get your levels checked (YES you are right it CAN be done!!) or maybe wait a few days and test again.
I dont want to be a wet cloth- but please be prepared to be told that you got "close" as i like to call it.

From my experiences i am trying to hold off until AF is actually late before testing because the stats are high for every woman to get "close" alot, and she would normally just think she got her period and think nothing of it- but when you are trying to concieve and you test BEFORE af is due- you tend to catch those "close calls" as faint lines and then get your period anyway. If we werent looking so hard we would never know- but it is really quite common.

However- i am a glutten for punishment and tested early this month and got a faint line- then AF. Will i ever learn??? LOL

Like i said- i dont mean to put a damper on things- i wish you all the best and i hope AF stays away for you and your faint lines get dark!!

Take care
StarBright
xoxox