when did you know and test?

This sort of strange coming here for help since it isnt for me.  But how fast did you know?  Here's the problem.  Sex happened on the 9th or so.  Condom broke.  Her period was/is due anytime.  she has taken 2 test and they both can back neg.  BUT she is tired all the time and sicky in the mornings.  Please dont take this the wrong way but we are hoping not.  She is only 94 pounds and 17 years old.  I am worried sick!!  Any thoughts would be great.

I knew because I was over a week late, I couldn't sleep through the night having to use the bathroom and being constantly thirsty.  I didn't find out until I was close to 6 weeks though.
It is possible that since her weight is low and she is younger her cycle could be off.  Stress can also delay the cycle, and stressing about a scare can be enough to do it.
It is still kind of early for a home test to come up positive, and most likely she would be getting the morning sickness yet, since that seems to start hitting in week 6 of pregnancy.  If she is truly worried, she will need to go to her normal OB or to a clinic, who may order a blood HCG test.  Good luck.

She goes in Friday for blood testing.  She has never been late even being 94 pounds.  She just started sleeping all the time, she pees (she says) 4 or 5 times between 6 am and 2 pm.  I'm not with her during the day.  I'm afraid this is a way to stay up with the girls at school.  She knows about 5 or more girls either pregnant or has a baby. 

I hope all the best for you.  I know despite being in my 30s, and my husband and I having stable jobs it is a scary prospect and we were hoping for this.  It's hard when a lot of the girls around you at that age have babies, or dream about all the love they will get from it.  The sad reality is, they take more love then they can give for a while and a lot of time.  I'm not saying they aren't worth it, but it will most likely be a real eye-opener.  The blood testing is the most sensitive, so you will hopefully soon have an answer.  I wish you the best though, no matter the answer you may get from the test.