Not having your period but spotting is int unusual during pregnancy.
In some cases when you are first pregnant you can still menstrate but I don't know how common that is.
You could have gotten pregnant on your period
Not normally
yes
You could still be pregnant. Light bleeding is common early in pregnancy. Take a test.
Yes.
No. If you still have you period, you cant be pregnant.
this means you are no longer pregnant. you were either not pregnant, or you have lost the baby.
If you had unprotected sex you could be pregnant, if you are still concerned take a test.
Even in the presence of bleeding, you could still be pregnant.
Yes, it is not as common to get pregnant while on your period, but you still can get pregnant. Sperm can live inside a women for a few days and it is definitely possible.
No you can't be pregnant and still have your period. You can have a light bleed but not a period. As for the whole negative test thing, it could be a false negative.