Thats why there is a time limit on them that they should be read in. Also sometimes they can show up positive the next day but thats due to an evaporation line. I dont think you need to worry that you are not pregnant. I have heard of a friend recently that got a false positive... That was because she is still nursing and there are still some levels of HCG in her body due to the nursing.. I never knew that but I guess that can cause a false positive.
So I am sure its safe to say you are pregnant.
Congrats sounds like u are expecting!
Sounds like you're pregnant, its more rare to have a false positive than a false negative. The tests are most accurate after I believe 5 minutes.. So, congrats!
No if you read the pregnancy test the day you take it. and you had positives, you're pregnant. if they sit too long or overnight it will probably give you false results. I wouldn't worry about what the day after tells you. so congratulations.