bleeding at almost 4 weeks & am I even pregnant?

I had Sex on Jan 25th and 27th. I start feeling "weird" almost right away. I just "felt" pregnant on the 28th ,feeling nauseous and my breasts felt swollen. This  continued for a few days (fiveish) and then I started with light pinkish bleeding on the 30th, which I thought was implantation bleeding.The following day I was bleeding heavily but not quite as heavy as my regular period. This lasted for about five more days. I started to think maybe I wasnt pregnant ,But I have the majority of the symptoms and alot of the things Im reading online say the bleeding could be normal. Also ,how long after intercourse can you take an at home pregnancy test? If the bleeding is normal ,what could be the reasons for it at this early of a stage in pregnancy and does it seem like Im even pregnant? I've also continued with dark brown thick discharge sense the heavy bleeding stopped. Today is February 6th