This month my period was acting weird, it started heavy at first, then the next day it was getting lighter and lighter. Then it was a pinkish brownish at the end. Could this mean something, or is it that my period was just being weird this month.

No, you won't have a regular period if you are pregnant. You can, however, have some bleeding in early pregnancy. Often times it will be a bit different from what your norm would be.

If you think there is the possibility of pregnancy, wait about a week or so and try a pregnancy test. It could be your period is just off this month, it could be pregnancy.