Possibly pregnant or period?

Addison

So I hooked up with this guy on July 5th and we haven’t done anything since. I’m on both control (wasn’t taking it at the correct time tho) and he was using a condom. I wasn’t paranoid or even thinking of a possibility of pregnancy until I got brown blood in my underwear two days in a row. Then, it just stopped. My boobs are sore and it says my period should start in 4 days but I’m just confused because I’ve never bled a few days before my period and then it just stopped? Also two days ago I took a pregnancy test and it came back negative but I’m not sure if I tested too early or not.