How accurate is a pregnancy test given at a hospital?

My test results were negative when I went to the hospital (they tested me before doing x-rays as a precaution), but I still haven't gotten my period. The month before, my birth control got off track, and I'm hoping that would contribute to being 2 weeks late. (and for anyone wondering, I was very careful, and used backup protection since my birth control was off track.) I'm just wondering if I should be concerned.

Here are the order of events:

1. You have sex and your egg gets fertilized.
2. Ten days later, your HCG levels are high enough to be detectable by a blood test. HCG is the hormone that is present in all pregnant women (Human Chorionic Gonadotropin).

If you had sex less than ten days before the hospital test, you might want to get re-checked. Of course, if you have had sex at all since that test, you could now be pregnant. Source(s): http://www.advancedfertility.com/earlypr...

Probably shouldn't be too concerned but I would test again in two weeks maybe. It could be just the off-track cycle or you may have not been pregnant at the time of the test.
I wouldn't be too concerned, Hospital pregnancy tests are very accurate. Your period being late is probably due to your birth control pills getting off track.
you arent pregnant