Period 2 months late

My girlfriend is 2 months late on her period after quitting birth control. We've taken about 8 home pregnancy tests within the last month or so; all have come up negative. We're going to planned parenthood tomorrow & hoping to get a blood test. Is it possible that she is pregnant although the tests have all come back negative? I know she's been very stressed out lately but I don't know if that would cause her to be this late? As far as symptoms go (if these even ARE symptoms) she's been somewhat constipated, nauseated every once in a while, somewhat moody but she usually is a rather moody person. I don't know if this is all just stress related because she's going through some difficult times right now, or if she's pregnant.

I'm just freaking out & would just like to know for sure.

[motherofan18month]

yes it is possible that she is preggo and not far enough along for the home tests to pick it up but if she hasn't had a period since  she came off birth control then it could also be that her body is trying to get back to normal..meaning she could have a period anytime, pregnancy comes with an aray of symptoms and some women dont have them at all.... but the best way to tell is have a blood test done or you can wait about 2 more weeks and test at home again...if it is negative again and there is no period then you should see about getting that blood test! best of luck to you and your girlfriend!!!!

[scutt]

Well she went to planned parenthood while i was working. They had her go in a cup, then basically just used a home pregnancy test from what it sounds like. It came back negative again. Aparently they were busy & the lady was a real b*tch to her & made her feel like she was stupid for coming in after so many tests had already come up negative.
She does not have insurance & i'm not sure how much a blood test costs. I'm not sure what the next step is. Wait even longer?? Thanks for the reply!