Could I Be Pregnant? Community

I am 21. Never had a baby before so I only have a slight idea of what to look for. I read online that there is such a thing as implantation bleeding. Today is sunday and last week around tue or wed I started have this brownish discharge and I thought it was my period. it lasted up until this morning. I woke up and went to the restroom and when i wiped i had that same discharge only with a little more red color and heavier. before it was so light i didnt even need a pad. and now it looks like a lot. so i am wearing a pad but it isnt getting dirty yet when i wipe it seems like there is a lot and the pad should be dirty but isnt. I read that the implantation bleeding is a sign that you are pregnant which i was almost positive i was pregnant yesterday because everything i was reading was coinciding with what was happening to me. but today i am not so sure. my initial question is:
Is it possible to have implantation bleeding and then still get a semi regular period if you conceived shortly before your next period? If not, what would cause me to have that brownish discharge and then a period right after it? just a note; my periods are usually heavy and if today i did infact start my period then yes it is more like my regular periods than that brown discharge but it is also a little less heavy than my regular periods still. I know all of this may be tmi but thanks for helping.