My period is late. I took a urine pregnancy test. The first one initially was invalid, that is not even the C line show up after 10 mins. But around 45 minutes later both the lines showed up indicating a positive result. Since then I've taken seven more pregnancy tests, all of them with the C line showing up immediately and the result showing negative all the seven times within a minute and remaining so for 5-10 mins. Positive result didn't appear in any of the seven. Can I be pregnant anyway?