Since you have taken several home pregnancy
tests and the results are not sure till now, you must do the test after one week from the date of your missed period.
Negative results can occur if you do the test before that. Also it can occur if your urine is diluted (due to drinking big amount of water). Blood tests are much more accurate in measuring the level of b-hCG
There is a possibility of being pregnant as there had been some positive results. There are many causes of a delayed period but the commonest one is pregnancy.
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